Order processing time: 3–5 business days
Bring the vibrant colors of a coral reef to life with the Hygger Marine One Coral Reef Light HG173, a full-spectrum saltwater aquarium LED light designed for nano reef aquariums, soft coral displays, LPS coral tanks, marine fish aquariums, and beautifully illuminated live rock aquascapes. Combining specialized blue, cool white, and UV-range LEDs with four selectable lighting channels, adjustable brightness, and an automatic 24/7 lighting cycle, the Hygger HG173 provides flexible reef illumination in a sleek, modern fixture.
Available in 19W and 35W models, the HG173 accommodates saltwater aquariums approximately 12–30 inches long, depending on the selected version. The smaller HG173-19W provides a manufacturer-described maximum coverage area of 20 × 20 inches, while the larger HG173-35W offers coverage up to 30 × 30 inches. Both models use a carefully selected marine lighting spectrum designed to enhance coral fluorescence, illuminate marine fish, and provide useful light for compatible photosynthetic corals.
The HG173 also features a built-in timer with 3-hour, 6-hour, 9-hour, and 12-hour settings, an optional additional three-hour moonlight period, ten brightness levels, power-failure memory, and a sturdy adjustable metal mounting bracket. Its slim aluminum alloy housing helps dissipate heat while maintaining a clean appearance above your aquarium.
Whether you're starting your first nano reef, upgrading an existing coral light, or creating a colorful marine display, the Hygger HG173 offers an accessible combination of reef-oriented lighting, convenient controls, and flexible installation.
Benefits of the Hygger Marine One Coral Reef Light HG173
Full-Spectrum Marine LED Lighting: Combines blue, cool white, and UV-range wavelengths for saltwater aquarium illumination.
Two Available Wattages: Choose the 19W or 35W model according to your aquarium size.
Designed for 12–30 Inch Aquariums: Provides lighting options for compact and medium-sized marine tanks.
Four Selectable Lighting Channels: Switch between Daylight, White & Blue, Blue + UV, and Moonlight.
24/7 Lighting Cycle: Creates gradual sunrise, daytime, sunset, and moonlight-style transitions.
Four Automatic Timer Settings: Choose 3H, 6H, 9H, or 12H lighting durations.
Optional Extended Moonlight: Add three hours of low-intensity nighttime illumination.
Ten Brightness Levels: Adjust output from 10% to 100% in 10% increments.
UV-Range LED Technology: Includes 395–400 nm LEDs to complement the marine lighting spectrum.
Enhanced Coral Fluorescence: Blue-rich lighting helps highlight fluorescent coral pigmentation.
Wide Lighting Coverage: Manufacturer-described coverage up to 20 × 20 inches or 30 × 30 inches.
Power-Failure Memory: Restores previously selected settings after an interruption in electrical power.
Adjustable Metal Mounting Bracket: Accommodates compatible rimmed and rimless aquariums.
Slim Aluminum Alloy Housing: Provides a modern appearance and effective passive heat dissipation.
Energy-Efficient Operation: Offers reef-oriented illumination with 19W or 35W power consumption.
Full-Spectrum LED Lighting for Saltwater Aquariums
The Hygger HG173 uses a combination of marine-oriented LED wavelengths selected for reef aquarium applications.
Its lighting system incorporates blue, cool white, and UV-range LEDs to create a spectrum suitable for viewing marine fish, live rock, and compatible photosynthetic corals.
Blue LEDs
Blue wavelengths are particularly important in reef aquarium lighting.
They contribute to the light available to photosynthetic organisms and help reveal fluorescent pigments in many coral species.
Cool White LEDs
Cool white LEDs create a balanced daylight appearance.
They help illuminate marine fish, coral structures, substrate, and aquarium decorations while improving overall viewing clarity.
UV-Range LEDs: 395–400 nm
The HG173 incorporates LEDs rated at approximately 395–400 nm.
These shorter wavelengths contribute to the fixture's marine spectrum and can enhance the appearance of fluorescent coral pigments.
Balanced Marine Lighting
The combination of blue, white, and UV-range LEDs allows users to choose different lighting appearances according to their aquarium's inhabitants and preferred presentation.
Important: The HG173's UV-range LEDs are part of its aquarium lighting system. They are not a UV sterilizer and are not intended for water disinfection.
Four Selectable Lighting Channels
The HG173 offers four lighting channels designed for different marine aquarium viewing conditions.
1. Daylight Channel
LED Combination: White + Blue + UV
Daylight Mode provides a bright, full-spectrum appearance for daytime aquarium viewing.
It helps reveal the colors of marine fish, live rock, and coral structures.
This channel is useful when you want a clear, natural-looking view of the aquarium.
2. White & Blue Channel
LED Combination: White + Blue + UV
The White & Blue channel provides an ocean-inspired lighting appearance.
Although it uses the same general LED color groups as Daylight Mode, it offers a different preset lighting balance.
This channel is suitable for marine aquarium viewing when a blue-influenced daylight appearance is preferred.
3. Blue Channel
LED Combination: Blue + UV
The Blue Channel emphasizes blue-rich illumination.
It can enhance the fluorescence of compatible corals, including zoanthids, mushroom corals, and selected LPS varieties.
This mode is especially attractive for showcasing fluorescent coral coloration.
4. Moonlight Channel
LED Combination: Blue + White
Moonlight Mode provides subdued illumination intended to resemble nighttime viewing conditions.
It can be used for decorative evening observation without maintaining full daytime brightness.
Selecting the Right Channel
Choose the channel according to coral requirements, desired color balance, and lighting intensity.
For photosynthetic corals, actual PAR and exposure duration matter more than the visual appearance of a channel alone.
Natural 24/7 Aquarium Lighting Cycle
The Hygger HG173 includes a built-in lighting cycle designed to create gradual changes in aquarium illumination.
Sunrise Simulation
The light can gradually transition into its daytime lighting period.
Daytime Illumination
The selected lighting channel provides illumination during the programmed photoperiod.
Sunset Simulation
The fixture transitions toward lower-intensity lighting as the programmed cycle ends.
Moonlight Effects
The optional moonlight feature provides subdued nighttime illumination.
Automatic Daily Repetition
Once configured, the lighting cycle repeats according to the selected timer.
Convenient Daily Operation
The automatic cycle helps maintain a predictable lighting routine without requiring a separate external timer.
Important: The HG173 provides preset timer durations and automatic lighting transitions. It is not an app-controlled fixture with individually programmable LED channels or a fully customizable minute-by-minute lighting schedule.
Four Built-In Timer Settings
The HG173 offers four timer durations through its inline controller.
3-Hour Timer
Provides a short programmed lighting period.
This can be useful for limited viewing periods or specific lighting arrangements.
6-Hour Timer
Provides a moderate lighting period.
A six-hour photoperiod may be a useful starting point when acclimating an aquarium to a new light.
9-Hour Timer
Provides a longer daily lighting period suitable for selected marine aquarium routines.
12-Hour Timer
Provides the longest available preset lighting duration.
Choosing the Best Timer
For many reef aquariums, a consistent photoperiod of approximately 8–10 hours of useful daytime illumination is a practical starting point.
However, appropriate duration depends on coral species, lighting intensity, aquarium depth, and the overall lighting program.
Optional Three-Hour Moonlight Extension
The HG173 includes a separate moonlight extension feature.
How It Works
Press and hold the 24Hrs timer button to activate or deactivate the additional moonlight period.
Moon ON Indicator
When the Moon ON indicator is illuminated, the light provides an additional three hours of moonlight-style illumination after the selected lighting period.
Decorative Evening Viewing
The feature allows aquarium owners to enjoy a subdued nighttime appearance after the main lighting cycle.
Automatic Operation
The optional moonlight extension becomes part of the recurring daily schedule.
Important Coral and Fish Care Consideration
Marine fish and corals generally benefit from a predictable period of darkness.
Avoid extending nighttime illumination unnecessarily if it interferes with the aquarium's normal resting cycle.
Ten Adjustable Brightness Levels
The Hygger HG173 allows users to adjust lighting intensity in ten steps.
Available brightness settings are:
10%: Very low-intensity illumination.
20%: Gentle lighting for acclimation.
30%: Reduced output for selected low-light applications.
40%: Moderate-low illumination.
50%: Half of the fixture's maximum output.
60%: Moderate illumination.
70%: Increased output.
80%: High-intensity illumination.
90%: Near-maximum output.
100%: Maximum available output.
Gradual Coral Acclimation
When replacing an older fixture, begin with reduced intensity and increase gradually.
Adjust for Aquarium Depth
Corals positioned deeper in the aquarium may receive less light than those near the surface.
Adjust for Coral Placement
The same aquarium can contain areas with different lighting intensities.
Avoid Excessive Light Exposure
More light is not always better.
Excessive intensity can stress corals, particularly when changes occur suddenly.
Two Available Hygger HG173 Models
The Marine One Coral Reef Light is available in two sizes.
HG173-19W – For 12–20 Inch Aquariums
The HG173-19W is the smaller model, designed for compact marine and nano reef aquariums.
Model Highlights:
Model: HG173-19W
Power Consumption: 19W
Recommended Aquarium Length: 12–20 inches / approximately 30–50 cm
Maximum Manufacturer-Described Coverage: 20 × 20 inches
Total LED Quantity: 96
Blue LEDs: 48
Cool White LEDs: 24
UV-Range LEDs: 24
UV Wavelength: 395–400 nm
Light Body Length: Approximately 10.9 inches / 27.7 cm
Light Body Width: Approximately 3.5 inches / 8.9 cm
Light Body Thickness: Approximately 0.6 inches / 1.5 cm
Operating Voltage: DC 24V
The 19W version is well suited to compatible small marine fish tanks, nano reefs, and low-to-medium-light coral displays.
HG173-35W – For 24–30 Inch Aquariums
The HG173-35W provides greater lighting output and coverage for larger marine aquariums.
Model Highlights:
Model: HG173-35W
Power Consumption: 35W
Recommended Aquarium Length: 24–30 inches / approximately 60–75 cm
Maximum Manufacturer-Described Coverage: 30 × 30 inches
Total LED Quantity: 216
Blue LEDs: 96
Cool White LEDs: 48
UV-Range LEDs: 72
UV Wavelength: 395–400 nm
Light Body Length: Approximately 21.3 inches / 54 cm
Light Body Width: Approximately 3.5 inches / 8.9 cm
Light Body Thickness: Approximately 0.6 inches / 1.5 cm
Operating Voltage: DC 24V
The 35W version is designed for compatible medium-sized marine aquariums requiring broader lighting coverage.
Important Model Selection Note
Hygger specifies a 12–20-inch aquarium range for the 19W model and a 24–30-inch range for the 35W model.
For aquariums between 20 and 24 inches long, check mounting dimensions and coral lighting requirements before selecting a fixture.
The manufacturer's maximum coverage figures describe potential light spread, not guaranteed uniform PAR across the entire footprint.
Reef Lighting for Soft Corals
The HG173 is designed for compatible soft coral aquariums.
Zoanthids
Blue-rich lighting can enhance the fluorescent colors of many zoanthid varieties.
Mushroom Corals
Mushroom corals are popular in nano reef aquariums and often tolerate relatively modest lighting.
Leather Corals
Selected leather coral species can be maintained under suitable lighting conditions.
Green Star Polyps
Green Star Polyps can display attractive fluorescence under appropriate blue-rich lighting.
Other Soft Corals
Compatibility depends on species, placement, water chemistry, and available light intensity.
Important Coral Care Note
Not every soft coral has the same lighting requirements.
Research individual species and monitor their response to changes in lighting.
Suitable for Selected LPS Coral Aquariums
The Hygger HG173 is also designed for compatible LPS coral systems.
Duncan Corals
Duncan corals are commonly maintained in reef aquariums with suitable moderate lighting.
Candy Cane Corals
Candy Cane corals can display attractive coloration under appropriate reef lighting.
Acan Corals
Some Acan varieties can thrive under moderate lighting conditions.
Hammer and Frogspawn Corals
These corals may be suitable when appropriate PAR, water movement, and placement requirements are met.
Important LPS Consideration
Avoid assuming that every LPS coral will receive sufficient light simply because the aquarium falls within the fixture's recommended length range.
Coral placement and actual PAR remain important.
SPS Coral Considerations
Some SPS corals require substantially higher light intensity than many soft and LPS corals.
Higher Lighting Requirements
Demanding SPS species may require higher PAR levels, particularly in deeper aquariums.
Verify Actual Light Intensity
Use a PAR meter or reliable tank-specific measurements when planning an SPS-dominant aquarium.
Consider Additional Fixtures
Larger or deeper aquariums may require additional lighting to achieve sufficient intensity and coverage.
Manufacturer's Primary Applications
Hygger primarily promotes the HG173 for soft corals, LPS corals, marine fish, and low-to-medium-light reef systems.
For demanding SPS systems, select lighting based on verified coral requirements rather than wattage alone.
Enhance Coral Fluorescence and Reef Colors
The HG173's blue-rich spectrum helps showcase the vibrant appearance of many reef aquarium organisms.
Fluorescent Coral Pigments
Certain coral pigments absorb shorter-wavelength light and emit visible fluorescence.
Colorful Zoanthids
The Blue + UV channel can emphasize bright fluorescent patterns.
Mushroom Coral Displays
Blue illumination can highlight the colors and textures of selected mushroom corals.
LPS Coral Coloration
Compatible LPS corals can display vivid coloration under suitable lighting.
Marine Fish Presentation
The Daylight and White & Blue channels provide attractive illumination for saltwater fish.
Live Rock Aquascapes
The broad light panel helps illuminate rock formations and coral structures.
Wide Lighting Coverage
The HG173 uses multiple LED beads distributed across a slim lighting panel.
HG173-19W Coverage
The manufacturer describes maximum light spread of approximately:
20 × 20 inches / 51 × 51 cm
HG173-35W Coverage
The manufacturer describes maximum light spread of approximately:
30 × 30 inches / 76 × 76 cm
Broad Aquarium Illumination
The distributed LED layout helps illuminate a wider area than a compact single-point spotlight.
Reduced Concentrated Shadows
Multiple LEDs can help soften some shadows around rocks and coral structures.
Coverage Depends on Installation
Actual lighting distribution depends on mounting height, aquarium depth, water clarity, and aquascape arrangement.
Important PAR Consideration
Coverage dimensions should not be interpreted as a guarantee that all corals within the stated area receive equal photosynthetically useful light.
Adjustable Metal Mounting Bracket
The HG173 includes a sturdy metal mounting bracket designed for convenient aquarium installation.
Clip-On Installation
The bracket attaches to the aquarium rim.
Rimless Aquarium Compatibility
Suitable for many rimless glass aquariums.
Rimmed Aquarium Compatibility
Also designed for compatible framed aquarium configurations.
Adjustable Height and Position
The mounting assembly includes a sliding track that allows the fixture's position to be adjusted.
Maximum Aquarium Rim Thickness
The manufacturer specifies compatibility with aquarium rims up to approximately:
1 inch / 2.54 cm
Secure Metal Construction
The bracket provides stable support for the light panel when installed correctly.
Important Installation Consideration
Measure the aquarium rim before purchasing.
Unusually shaped frames, lids, and reinforced edges may affect compatibility.
Slim Aluminum Alloy Housing
The HG173 features a thin aluminum alloy lighting body.
Approximately 0.6-Inch Thickness
The slim design creates a modern appearance above the aquarium.
Passive Heat Dissipation
Aluminum helps transfer heat away from the LED components.
Durable Construction
The metal housing supports everyday aquarium use.
Marine-Oriented Materials
Hygger describes the fixture as incorporating corrosion-resistant construction.
Easy Exterior Cleaning
The accessible housing can be wiped clean after disconnecting electrical power.
Attractive Aquarium Presentation
The streamlined design complements open-top marine and reef aquariums.
Power-Failure Memory Function
The Hygger HG173 includes a memory function designed to restore previous settings following a power interruption.
Retains Lighting Preferences
The fixture remembers previously selected operating settings.
Convenient Restart
The light can restore its settings when electrical power returns.
Reduced Reprogramming
The memory function helps reduce the need to reselect channels and brightness after an interruption.
Important Timer Consideration
After an outage, verify that the automatic lighting schedule remains aligned with your preferred daily start time.
The memory function should not be treated as a guarantee that the original timing remains synchronized through every power interruption.
Energy-Efficient Marine LED Lighting
The HG173 uses LED technology to provide reef-oriented illumination with relatively low power consumption.
19W Model
Designed for compact marine aquariums.
35W Model
Provides increased lighting output for larger marine displays.
Adjustable Brightness
Reduce intensity when maximum output is unnecessary.
Automatic Timer
The built-in timer helps prevent unnecessary operation outside the selected photoperiod.
Aluminum Heat Dissipation
The housing helps manage operating temperatures without requiring a bulky lighting enclosure.
Choosing the Right Hygger HG173 Model
Choose HG173-19W When
Your aquarium is approximately 12–20 inches long.
You maintain a compatible nano reef.
You keep selected soft corals or LPS corals.
You want compact marine LED lighting.
A maximum 20 × 20-inch light spread is appropriate.
Choose HG173-35W When
Your aquarium is approximately 24–30 inches long.
You need broader lighting coverage.
You maintain a medium-sized saltwater aquarium.
You want more LED output for compatible coral displays.
A maximum 30 × 30-inch light spread is appropriate.
Consider Aquarium Depth
A deeper aquarium generally requires more careful evaluation of coral lighting intensity.
Consider Coral Requirements
Choose the fixture according to the species you intend to keep.
Consider Rockwork
Large rock structures can create shaded areas.
Consider Additional Lighting
Longer, wider, or deeper aquariums may require multiple fixtures.
Suitable Aquarium Applications
The Hygger Marine One Coral Reef Light HG173 is suitable for:
Nano reef aquariums
Small saltwater aquariums
Medium-sized marine aquariums
Soft coral reef tanks
Compatible LPS coral aquariums
Zoanthid displays
Mushroom coral aquariums
Marine fish-only aquariums
Fish-only-with-live-rock aquariums
Live rock aquascapes
Low-to-medium-light reef systems
Compatible mixed reef aquariums
Rimmed saltwater aquariums
Rimless marine aquariums
Aquariums requiring blue-rich reef lighting
Aquariums requiring adjustable brightness
Aquariums requiring automatic daily lighting cycles
Aquariums requiring sunrise and sunset-style transitions
Aquariums requiring optional moonlight illumination
Aquariums requiring compact aluminum LED fixtures
For demanding SPS-dominant reef aquariums, verify actual PAR and consider more powerful or supplemental lighting when necessary.
How to Use the Four Lighting Channels
Turn on the fixture: Press the power button on the inline controller.
Locate the Menu button: Find the button marked M.
Select Daylight: Choose the bright full-spectrum daytime channel.
Select White & Blue: Choose the ocean-inspired lighting balance.
Select Blue: Activate the blue-rich channel.
Select Moonlight: Choose the subdued nighttime channel.
Adjust brightness: Use the dimmer control to select the desired intensity.
Set the timer: Choose the appropriate automatic lighting duration.
Observe the aquarium: Confirm that the selected channel suits your coral and fish requirements.
How to Set the Automatic 24/7 Timer
Connect the fixture to power.
Press the ON/OFF button to turn on the light.
Press the Menu button to select the preferred lighting channel.
Adjust the brightness using the dimmer control.
Press the timer button to cycle through the available durations.
Choose 3H, 6H, 9H, or 12H.
Confirm the selected timer indicator.
Activate optional moonlight if desired by pressing and holding the 24Hrs button.
Check the Moon ON indicator to confirm the additional three-hour moonlight period.
Allow the schedule to repeat daily.
Important Scheduling Tip
Set the timer at the time you want the daily lighting cycle to begin.
The HG173 uses controller-based scheduling rather than a separately programmable clock.
How to Activate the Extended Moonlight Feature
Turn on the HG173.
Select the preferred main lighting channel.
Choose the desired timer duration.
Press and hold the 24Hrs button.
Confirm that the Moon ON indicator illuminates.
The fixture adds approximately three hours of low-intensity moonlight after the main lighting period.
Press and hold the button again to deactivate the extension when required.
Installation and Usage Guidelines
Select the correct model: Choose HG173-19W or HG173-35W according to aquarium size.
Inspect the components: Check the light panel, controller, adapter, mounting bracket, and manual.
Choose the mounting location: Select a stable section of aquarium rim.
Check rim thickness: Ensure the mounting surface is compatible with the one-inch clamp limit.
Prepare the metal bracket: Loosen the mounting hardware as instructed.
Slide the light into the metal clamp: Position the fixture within the mounting assembly.
Insert the metal screw: Secure it in the middle of the designated slot.
Tighten the screw: Hold the light securely without overtightening.
Install the two plastic screws: Secure the light panel to the bracket.
Position the bracket: Attach the mounting assembly to the aquarium rim.
Adjust the fixture: Use the sliding mechanism to position the light.
Check stability: Confirm the fixture cannot slip into the aquarium.
Arrange the electrical cables: Keep connections away from water and salt spray.
Create a drip loop: Prevent water from reaching the electrical outlet.
Connect the DC adapter: Use the supplied power supply.
Turn on the light: Press the power button.
Select a lighting channel: Choose the preferred marine lighting mode.
Adjust brightness: Start with an appropriate intensity.
Set the timer: Choose 3, 6, 9, or 12 hours.
Monitor coral response: Make gradual adjustments when necessary.
Tips for Successful Reef Aquarium Lighting
Start With Moderate Brightness
Avoid immediately using maximum output when introducing a new fixture.
Acclimate Corals Gradually
Sudden changes in lighting can stress photosynthetic corals.
Maintain a Consistent Photoperiod
Regular daily lighting helps create predictable conditions.
Consider PAR Requirements
Coral growth depends on the intensity and quality of light reaching each colony.
Maintain Stable Water Chemistry
Corals also require suitable salinity, alkalinity, calcium, magnesium, temperature, and nutrient levels.
Maintain Appropriate Water Movement
Good circulation helps support coral health and nutrient exchange.
Avoid Excessive Nighttime Illumination
Provide a suitable dark period.
Monitor Coral Condition
Observe polyp extension, coloration, and tissue condition.
Maintenance and Cleaning Guidelines
Disconnect Power
Always unplug the fixture before cleaning.
Allow the Housing to Cool
Wait until the light is cool enough to handle safely.
Clean the Aluminum Housing
Use a soft, dry cloth to remove dust.
Remove Salt Deposits
Carefully clean accessible surfaces without allowing water into electrical components.
Inspect the LED Cover
Remove dust or deposits that could reduce light transmission.
Check the Mounting Bracket
Ensure all mounting screws remain secure.
Inspect the Sliding Track
Confirm that the light remains properly positioned.
Check Electrical Connections
Look for visible cable damage or corrosion.
Keep the Adapter Dry
Do not expose the power adapter or controller to aquarium water.
Avoid Harsh Chemicals
Do not use abrasive cleaners, household detergents, or solvents.
Troubleshooting Guide
Light Does Not Turn On
Check the power outlet.
Confirm the adapter is connected.
Inspect the controller and cable connections.
Lighting Channel Is Incorrect
Press the Menu button to cycle through the four channels.
Brightness Is Too Low
Increase the dimmer setting.
Check the selected lighting channel.
Light Turns Off Earlier Than Expected
Review the 3H, 6H, 9H, or 12H timer setting.
Moonlight Remains On After the Main Cycle
Check whether the Moon ON indicator is active.
Deactivate the additional moonlight period if necessary.
Schedule Changes After Power Loss
Check the timer and lighting settings after electrical power returns.
Light Coverage Is Uneven
Adjust the mounting position.
Evaluate the aquarium's width, depth, and rockwork.
Corals Show Signs of Light Stress
Reduce brightness and review placement.
Corals Receive Insufficient Light
Check aquarium depth and coral positioning.
Consider PAR measurement or additional lighting.
Mounting Bracket Feels Loose
Check the metal and plastic mounting screws.
Confirm that the aquarium rim is compatible.
Important Safety Guidelines
Install the HG173 securely above the aquarium.
Do not submerge the fixture, controller, or adapter.
Keep electrical connections dry.
Avoid exposing the fixture to excessive salt spray.
Disconnect power before cleaning or repositioning.
Allow the housing to cool before handling.
Do not use the fixture with damaged wiring.
Secure the mounting bracket carefully.
Do not overtighten mounting screws against aquarium glass.
Remove the metal and plastic mounting screws before detaching the light from its bracket.
Use only a compatible manufacturer-approved power adapter.
Create a drip loop in electrical cables.
Use an appropriately protected electrical outlet.
Avoid looking directly into the illuminated LEDs, particularly the blue and UV-range components.
Do not attempt unauthorized electrical repairs.
Keep electrical equipment away from children.
Follow the manufacturer's user manual.
Product Specifications
Brand: Hygger
Product Name: Marine One Coral Reef Light
Model Series: HG173
Available Models: HG173-19W and HG173-35W
Product Type: Full-Spectrum Marine Aquarium LED Light
Available Wattages: 19W and 35W
Recommended Aquarium Length: 12–30 Inches, Depending on Model
LED Colors: Blue, Cool White, and UV-Range
UV-Range Wavelength: 395–400 nm
Lighting Channels: Daylight, White & Blue, Blue + UV, and Moonlight
Automatic 24/7 Lighting Cycle: Yes
Sunrise and Sunset-Style Transitions: Yes
Timer Settings: 3H, 6H, 9H, and 12H
Optional Extended Moonlight: Additional 3 Hours
Brightness Adjustment: 10%–100%
Brightness Levels: 10
Power-Failure Memory: Yes
Controller Type: Inline Physical Controller
Smartphone App Control: No
Housing Material: Aluminum Alloy
Light Body Thickness: Approximately 0.6 Inches / 1.5 cm
Mounting Method: Adjustable Metal Clip-On Bracket
Compatible Aquarium Types: Rimmed and Rimless
Maximum Aquarium Rim Thickness: Approximately 1 Inch / 2.54 cm
AC Adapter Input: 100–240V, 50–60Hz
Operating Voltage: DC 24V
Power Cord Sections: Approximately 4.9 ft + 4.9 ft + 1.6 ft
Installation Type: Above-Aquarium
Submersible: No
Primary Applications: Saltwater Aquariums, Soft Coral Tanks, LPS Coral Displays, and Marine Fish Tanks
HG173-19W Specifications
Model: HG173-19W
Power Consumption: 19W
Total LED Quantity: 96
Blue LEDs: 48
Cool White LEDs: 24
UV-Range LEDs: 24
UV Wavelength: 395–400 nm
Recommended Aquarium Length: 12–20 Inches / 30–50 cm
Maximum Manufacturer-Described Light Coverage: 20 × 20 Inches
Light Body Dimensions: Approximately 10.9 × 3.5 × 0.6 Inches
Overall Manufacturer Manual Dimensions Including Mounting Assembly: Approximately 12 × 3.2 × 12 Inches
Operating Voltage: DC 24V
HG173-35W Specifications
Model: HG173-35W
Power Consumption: 35W
Total LED Quantity: 216
Blue LEDs: 96
Cool White LEDs: 48
UV-Range LEDs: 72
UV Wavelength: 395–400 nm
Recommended Aquarium Length: 24–30 Inches / 60–75 cm
Maximum Manufacturer-Described Light Coverage: 30 × 30 Inches
Light Body Dimensions: Approximately 21.3 × 3.5 × 0.6 Inches
Overall Manufacturer Manual Dimensions Including Mounting Assembly: Approximately 24 × 3.2 × 12 Inches
Operating Voltage: DC 24V
Specifications are based on Hygger's official product information and HG173 user manual. The manufacturer publishes both compact light-body dimensions and larger assembled dimensions; these measurements refer to different parts of the installed fixture. Published coverage values describe light spread and do not guarantee uniform PAR or suitability for every coral species.
Package Includes
Each HG173 model includes:
The mounting assembly uses securing screws as described in the installation instructions.
Beautiful, Customizable Lighting for Marine and Reef Aquariums
The Hygger Marine One Coral Reef Light HG173 is an excellent choice for marine aquarium enthusiasts who want vibrant coral illumination, adjustable brightness, and convenient automatic lighting without a complicated control system.
Its marine-oriented combination of blue, cool white, and UV-range LEDs helps enhance coral fluorescence while providing attractive illumination for saltwater fish, live rock, and compatible soft and LPS corals.
With two available wattages, four lighting channels, ten brightness settings, a programmable-duration 24/7 cycle, and optional extended moonlight, the HG173 offers practical flexibility for different marine aquarium displays.
The slim aluminum alloy housing and adjustable metal mounting bracket provide a clean, modern appearance, while the power-failure memory function adds everyday convenience.
Whether you're setting up a nano reef, maintaining a colorful soft coral aquarium, or upgrading the lighting on a medium-sized saltwater display, the HG173 combines marine-focused LED technology with straightforward operation.
Order the Hygger Marine One Coral Reef Light HG173 today and enjoy vivid coral coloration, customizable full-spectrum reef lighting, and convenient automatic day-and-night illumination.
Order processing time: 3–5 business days
Bring the vibrant colors of a coral reef to life with the Hygger Marine One Coral Reef Light HG173, a full-spectrum saltwater aquarium LED light designed for nano reef aquariums, soft coral displays, LPS coral tanks, marine fish aquariums, and beautifully illuminated live rock aquascapes. Combining specialized blue, cool white, and UV-range LEDs with four selectable lighting channels, adjustable brightness, and an automatic 24/7 lighting cycle, the Hygger HG173 provides flexible reef illumination in a sleek, modern fixture.
Available in 19W and 35W models, the HG173 accommodates saltwater aquariums approximately 12–30 inches long, depending on the selected version. The smaller HG173-19W provides a manufacturer-described maximum coverage area of 20 × 20 inches, while the larger HG173-35W offers coverage up to 30 × 30 inches. Both models use a carefully selected marine lighting spectrum designed to enhance coral fluorescence, illuminate marine fish, and provide useful light for compatible photosynthetic corals.
The HG173 also features a built-in timer with 3-hour, 6-hour, 9-hour, and 12-hour settings, an optional additional three-hour moonlight period, ten brightness levels, power-failure memory, and a sturdy adjustable metal mounting bracket. Its slim aluminum alloy housing helps dissipate heat while maintaining a clean appearance above your aquarium.
Whether you're starting your first nano reef, upgrading an existing coral light, or creating a colorful marine display, the Hygger HG173 offers an accessible combination of reef-oriented lighting, convenient controls, and flexible installation.
Benefits of the Hygger Marine One Coral Reef Light HG173
Full-Spectrum Marine LED Lighting: Combines blue, cool white, and UV-range wavelengths for saltwater aquarium illumination.
Two Available Wattages: Choose the 19W or 35W model according to your aquarium size.
Designed for 12–30 Inch Aquariums: Provides lighting options for compact and medium-sized marine tanks.
Four Selectable Lighting Channels: Switch between Daylight, White & Blue, Blue + UV, and Moonlight.
24/7 Lighting Cycle: Creates gradual sunrise, daytime, sunset, and moonlight-style transitions.
Four Automatic Timer Settings: Choose 3H, 6H, 9H, or 12H lighting durations.
Optional Extended Moonlight: Add three hours of low-intensity nighttime illumination.
Ten Brightness Levels: Adjust output from 10% to 100% in 10% increments.
UV-Range LED Technology: Includes 395–400 nm LEDs to complement the marine lighting spectrum.
Enhanced Coral Fluorescence: Blue-rich lighting helps highlight fluorescent coral pigmentation.
Wide Lighting Coverage: Manufacturer-described coverage up to 20 × 20 inches or 30 × 30 inches.
Power-Failure Memory: Restores previously selected settings after an interruption in electrical power.
Adjustable Metal Mounting Bracket: Accommodates compatible rimmed and rimless aquariums.
Slim Aluminum Alloy Housing: Provides a modern appearance and effective passive heat dissipation.
Energy-Efficient Operation: Offers reef-oriented illumination with 19W or 35W power consumption.
Full-Spectrum LED Lighting for Saltwater Aquariums
The Hygger HG173 uses a combination of marine-oriented LED wavelengths selected for reef aquarium applications.
Its lighting system incorporates blue, cool white, and UV-range LEDs to create a spectrum suitable for viewing marine fish, live rock, and compatible photosynthetic corals.
Blue LEDs
Blue wavelengths are particularly important in reef aquarium lighting.
They contribute to the light available to photosynthetic organisms and help reveal fluorescent pigments in many coral species.
Cool White LEDs
Cool white LEDs create a balanced daylight appearance.
They help illuminate marine fish, coral structures, substrate, and aquarium decorations while improving overall viewing clarity.
UV-Range LEDs: 395–400 nm
The HG173 incorporates LEDs rated at approximately 395–400 nm.
These shorter wavelengths contribute to the fixture's marine spectrum and can enhance the appearance of fluorescent coral pigments.
Balanced Marine Lighting
The combination of blue, white, and UV-range LEDs allows users to choose different lighting appearances according to their aquarium's inhabitants and preferred presentation.
Important: The HG173's UV-range LEDs are part of its aquarium lighting system. They are not a UV sterilizer and are not intended for water disinfection.
Four Selectable Lighting Channels
The HG173 offers four lighting channels designed for different marine aquarium viewing conditions.
1. Daylight Channel
LED Combination: White + Blue + UV
Daylight Mode provides a bright, full-spectrum appearance for daytime aquarium viewing.
It helps reveal the colors of marine fish, live rock, and coral structures.
This channel is useful when you want a clear, natural-looking view of the aquarium.
2. White & Blue Channel
LED Combination: White + Blue + UV
The White & Blue channel provides an ocean-inspired lighting appearance.
Although it uses the same general LED color groups as Daylight Mode, it offers a different preset lighting balance.
This channel is suitable for marine aquarium viewing when a blue-influenced daylight appearance is preferred.
3. Blue Channel
LED Combination: Blue + UV
The Blue Channel emphasizes blue-rich illumination.
It can enhance the fluorescence of compatible corals, including zoanthids, mushroom corals, and selected LPS varieties.
This mode is especially attractive for showcasing fluorescent coral coloration.
4. Moonlight Channel
LED Combination: Blue + White
Moonlight Mode provides subdued illumination intended to resemble nighttime viewing conditions.
It can be used for decorative evening observation without maintaining full daytime brightness.
Selecting the Right Channel
Choose the channel according to coral requirements, desired color balance, and lighting intensity.
For photosynthetic corals, actual PAR and exposure duration matter more than the visual appearance of a channel alone.
Natural 24/7 Aquarium Lighting Cycle
The Hygger HG173 includes a built-in lighting cycle designed to create gradual changes in aquarium illumination.
Sunrise Simulation
The light can gradually transition into its daytime lighting period.
Daytime Illumination
The selected lighting channel provides illumination during the programmed photoperiod.
Sunset Simulation
The fixture transitions toward lower-intensity lighting as the programmed cycle ends.
Moonlight Effects
The optional moonlight feature provides subdued nighttime illumination.
Automatic Daily Repetition
Once configured, the lighting cycle repeats according to the selected timer.
Convenient Daily Operation
The automatic cycle helps maintain a predictable lighting routine without requiring a separate external timer.
Important: The HG173 provides preset timer durations and automatic lighting transitions. It is not an app-controlled fixture with individually programmable LED channels or a fully customizable minute-by-minute lighting schedule.
Four Built-In Timer Settings
The HG173 offers four timer durations through its inline controller.
3-Hour Timer
Provides a short programmed lighting period.
This can be useful for limited viewing periods or specific lighting arrangements.
6-Hour Timer
Provides a moderate lighting period.
A six-hour photoperiod may be a useful starting point when acclimating an aquarium to a new light.
9-Hour Timer
Provides a longer daily lighting period suitable for selected marine aquarium routines.
12-Hour Timer
Provides the longest available preset lighting duration.
Choosing the Best Timer
For many reef aquariums, a consistent photoperiod of approximately 8–10 hours of useful daytime illumination is a practical starting point.
However, appropriate duration depends on coral species, lighting intensity, aquarium depth, and the overall lighting program.
Optional Three-Hour Moonlight Extension
The HG173 includes a separate moonlight extension feature.
How It Works
Press and hold the 24Hrs timer button to activate or deactivate the additional moonlight period.
Moon ON Indicator
When the Moon ON indicator is illuminated, the light provides an additional three hours of moonlight-style illumination after the selected lighting period.
Decorative Evening Viewing
The feature allows aquarium owners to enjoy a subdued nighttime appearance after the main lighting cycle.
Automatic Operation
The optional moonlight extension becomes part of the recurring daily schedule.
Important Coral and Fish Care Consideration
Marine fish and corals generally benefit from a predictable period of darkness.
Avoid extending nighttime illumination unnecessarily if it interferes with the aquarium's normal resting cycle.
Ten Adjustable Brightness Levels
The Hygger HG173 allows users to adjust lighting intensity in ten steps.
Available brightness settings are:
10%: Very low-intensity illumination.
20%: Gentle lighting for acclimation.
30%: Reduced output for selected low-light applications.
40%: Moderate-low illumination.
50%: Half of the fixture's maximum output.
60%: Moderate illumination.
70%: Increased output.
80%: High-intensity illumination.
90%: Near-maximum output.
100%: Maximum available output.
Gradual Coral Acclimation
When replacing an older fixture, begin with reduced intensity and increase gradually.
Adjust for Aquarium Depth
Corals positioned deeper in the aquarium may receive less light than those near the surface.
Adjust for Coral Placement
The same aquarium can contain areas with different lighting intensities.
Avoid Excessive Light Exposure
More light is not always better.
Excessive intensity can stress corals, particularly when changes occur suddenly.
Two Available Hygger HG173 Models
The Marine One Coral Reef Light is available in two sizes.
HG173-19W – For 12–20 Inch Aquariums
The HG173-19W is the smaller model, designed for compact marine and nano reef aquariums.
Model Highlights:
Model: HG173-19W
Power Consumption: 19W
Recommended Aquarium Length: 12–20 inches / approximately 30–50 cm
Maximum Manufacturer-Described Coverage: 20 × 20 inches
Total LED Quantity: 96
Blue LEDs: 48
Cool White LEDs: 24
UV-Range LEDs: 24
UV Wavelength: 395–400 nm
Light Body Length: Approximately 10.9 inches / 27.7 cm
Light Body Width: Approximately 3.5 inches / 8.9 cm
Light Body Thickness: Approximately 0.6 inches / 1.5 cm
Operating Voltage: DC 24V
The 19W version is well suited to compatible small marine fish tanks, nano reefs, and low-to-medium-light coral displays.
HG173-35W – For 24–30 Inch Aquariums
The HG173-35W provides greater lighting output and coverage for larger marine aquariums.
Model Highlights:
Model: HG173-35W
Power Consumption: 35W
Recommended Aquarium Length: 24–30 inches / approximately 60–75 cm
Maximum Manufacturer-Described Coverage: 30 × 30 inches
Total LED Quantity: 216
Blue LEDs: 96
Cool White LEDs: 48
UV-Range LEDs: 72
UV Wavelength: 395–400 nm
Light Body Length: Approximately 21.3 inches / 54 cm
Light Body Width: Approximately 3.5 inches / 8.9 cm
Light Body Thickness: Approximately 0.6 inches / 1.5 cm
Operating Voltage: DC 24V
The 35W version is designed for compatible medium-sized marine aquariums requiring broader lighting coverage.
Important Model Selection Note
Hygger specifies a 12–20-inch aquarium range for the 19W model and a 24–30-inch range for the 35W model.
For aquariums between 20 and 24 inches long, check mounting dimensions and coral lighting requirements before selecting a fixture.
The manufacturer's maximum coverage figures describe potential light spread, not guaranteed uniform PAR across the entire footprint.
Reef Lighting for Soft Corals
The HG173 is designed for compatible soft coral aquariums.
Zoanthids
Blue-rich lighting can enhance the fluorescent colors of many zoanthid varieties.
Mushroom Corals
Mushroom corals are popular in nano reef aquariums and often tolerate relatively modest lighting.
Leather Corals
Selected leather coral species can be maintained under suitable lighting conditions.
Green Star Polyps
Green Star Polyps can display attractive fluorescence under appropriate blue-rich lighting.
Other Soft Corals
Compatibility depends on species, placement, water chemistry, and available light intensity.
Important Coral Care Note
Not every soft coral has the same lighting requirements.
Research individual species and monitor their response to changes in lighting.
Suitable for Selected LPS Coral Aquariums
The Hygger HG173 is also designed for compatible LPS coral systems.
Duncan Corals
Duncan corals are commonly maintained in reef aquariums with suitable moderate lighting.
Candy Cane Corals
Candy Cane corals can display attractive coloration under appropriate reef lighting.
Acan Corals
Some Acan varieties can thrive under moderate lighting conditions.
Hammer and Frogspawn Corals
These corals may be suitable when appropriate PAR, water movement, and placement requirements are met.
Important LPS Consideration
Avoid assuming that every LPS coral will receive sufficient light simply because the aquarium falls within the fixture's recommended length range.
Coral placement and actual PAR remain important.
SPS Coral Considerations
Some SPS corals require substantially higher light intensity than many soft and LPS corals.
Higher Lighting Requirements
Demanding SPS species may require higher PAR levels, particularly in deeper aquariums.
Verify Actual Light Intensity
Use a PAR meter or reliable tank-specific measurements when planning an SPS-dominant aquarium.
Consider Additional Fixtures
Larger or deeper aquariums may require additional lighting to achieve sufficient intensity and coverage.
Manufacturer's Primary Applications
Hygger primarily promotes the HG173 for soft corals, LPS corals, marine fish, and low-to-medium-light reef systems.
For demanding SPS systems, select lighting based on verified coral requirements rather than wattage alone.
Enhance Coral Fluorescence and Reef Colors
The HG173's blue-rich spectrum helps showcase the vibrant appearance of many reef aquarium organisms.
Fluorescent Coral Pigments
Certain coral pigments absorb shorter-wavelength light and emit visible fluorescence.
Colorful Zoanthids
The Blue + UV channel can emphasize bright fluorescent patterns.
Mushroom Coral Displays
Blue illumination can highlight the colors and textures of selected mushroom corals.
LPS Coral Coloration
Compatible LPS corals can display vivid coloration under suitable lighting.
Marine Fish Presentation
The Daylight and White & Blue channels provide attractive illumination for saltwater fish.
Live Rock Aquascapes
The broad light panel helps illuminate rock formations and coral structures.
Wide Lighting Coverage
The HG173 uses multiple LED beads distributed across a slim lighting panel.
HG173-19W Coverage
The manufacturer describes maximum light spread of approximately:
20 × 20 inches / 51 × 51 cm
HG173-35W Coverage
The manufacturer describes maximum light spread of approximately:
30 × 30 inches / 76 × 76 cm
Broad Aquarium Illumination
The distributed LED layout helps illuminate a wider area than a compact single-point spotlight.
Reduced Concentrated Shadows
Multiple LEDs can help soften some shadows around rocks and coral structures.
Coverage Depends on Installation
Actual lighting distribution depends on mounting height, aquarium depth, water clarity, and aquascape arrangement.
Important PAR Consideration
Coverage dimensions should not be interpreted as a guarantee that all corals within the stated area receive equal photosynthetically useful light.
Adjustable Metal Mounting Bracket
The HG173 includes a sturdy metal mounting bracket designed for convenient aquarium installation.
Clip-On Installation
The bracket attaches to the aquarium rim.
Rimless Aquarium Compatibility
Suitable for many rimless glass aquariums.
Rimmed Aquarium Compatibility
Also designed for compatible framed aquarium configurations.
Adjustable Height and Position
The mounting assembly includes a sliding track that allows the fixture's position to be adjusted.
Maximum Aquarium Rim Thickness
The manufacturer specifies compatibility with aquarium rims up to approximately:
1 inch / 2.54 cm
Secure Metal Construction
The bracket provides stable support for the light panel when installed correctly.
Important Installation Consideration
Measure the aquarium rim before purchasing.
Unusually shaped frames, lids, and reinforced edges may affect compatibility.
Slim Aluminum Alloy Housing
The HG173 features a thin aluminum alloy lighting body.
Approximately 0.6-Inch Thickness
The slim design creates a modern appearance above the aquarium.
Passive Heat Dissipation
Aluminum helps transfer heat away from the LED components.
Durable Construction
The metal housing supports everyday aquarium use.
Marine-Oriented Materials
Hygger describes the fixture as incorporating corrosion-resistant construction.
Easy Exterior Cleaning
The accessible housing can be wiped clean after disconnecting electrical power.
Attractive Aquarium Presentation
The streamlined design complements open-top marine and reef aquariums.
Power-Failure Memory Function
The Hygger HG173 includes a memory function designed to restore previous settings following a power interruption.
Retains Lighting Preferences
The fixture remembers previously selected operating settings.
Convenient Restart
The light can restore its settings when electrical power returns.
Reduced Reprogramming
The memory function helps reduce the need to reselect channels and brightness after an interruption.
Important Timer Consideration
After an outage, verify that the automatic lighting schedule remains aligned with your preferred daily start time.
The memory function should not be treated as a guarantee that the original timing remains synchronized through every power interruption.
Energy-Efficient Marine LED Lighting
The HG173 uses LED technology to provide reef-oriented illumination with relatively low power consumption.
19W Model
Designed for compact marine aquariums.
35W Model
Provides increased lighting output for larger marine displays.
Adjustable Brightness
Reduce intensity when maximum output is unnecessary.
Automatic Timer
The built-in timer helps prevent unnecessary operation outside the selected photoperiod.
Aluminum Heat Dissipation
The housing helps manage operating temperatures without requiring a bulky lighting enclosure.
Choosing the Right Hygger HG173 Model
Choose HG173-19W When
Your aquarium is approximately 12–20 inches long.
You maintain a compatible nano reef.
You keep selected soft corals or LPS corals.
You want compact marine LED lighting.
A maximum 20 × 20-inch light spread is appropriate.
Choose HG173-35W When
Your aquarium is approximately 24–30 inches long.
You need broader lighting coverage.
You maintain a medium-sized saltwater aquarium.
You want more LED output for compatible coral displays.
A maximum 30 × 30-inch light spread is appropriate.
Consider Aquarium Depth
A deeper aquarium generally requires more careful evaluation of coral lighting intensity.
Consider Coral Requirements
Choose the fixture according to the species you intend to keep.
Consider Rockwork
Large rock structures can create shaded areas.
Consider Additional Lighting
Longer, wider, or deeper aquariums may require multiple fixtures.
Suitable Aquarium Applications
The Hygger Marine One Coral Reef Light HG173 is suitable for:
Nano reef aquariums
Small saltwater aquariums
Medium-sized marine aquariums
Soft coral reef tanks
Compatible LPS coral aquariums
Zoanthid displays
Mushroom coral aquariums
Marine fish-only aquariums
Fish-only-with-live-rock aquariums
Live rock aquascapes
Low-to-medium-light reef systems
Compatible mixed reef aquariums
Rimmed saltwater aquariums
Rimless marine aquariums
Aquariums requiring blue-rich reef lighting
Aquariums requiring adjustable brightness
Aquariums requiring automatic daily lighting cycles
Aquariums requiring sunrise and sunset-style transitions
Aquariums requiring optional moonlight illumination
Aquariums requiring compact aluminum LED fixtures
For demanding SPS-dominant reef aquariums, verify actual PAR and consider more powerful or supplemental lighting when necessary.
How to Use the Four Lighting Channels
Turn on the fixture: Press the power button on the inline controller.
Locate the Menu button: Find the button marked M.
Select Daylight: Choose the bright full-spectrum daytime channel.
Select White & Blue: Choose the ocean-inspired lighting balance.
Select Blue: Activate the blue-rich channel.
Select Moonlight: Choose the subdued nighttime channel.
Adjust brightness: Use the dimmer control to select the desired intensity.
Set the timer: Choose the appropriate automatic lighting duration.
Observe the aquarium: Confirm that the selected channel suits your coral and fish requirements.
How to Set the Automatic 24/7 Timer
Connect the fixture to power.
Press the ON/OFF button to turn on the light.
Press the Menu button to select the preferred lighting channel.
Adjust the brightness using the dimmer control.
Press the timer button to cycle through the available durations.
Choose 3H, 6H, 9H, or 12H.
Confirm the selected timer indicator.
Activate optional moonlight if desired by pressing and holding the 24Hrs button.
Check the Moon ON indicator to confirm the additional three-hour moonlight period.
Allow the schedule to repeat daily.
Important Scheduling Tip
Set the timer at the time you want the daily lighting cycle to begin.
The HG173 uses controller-based scheduling rather than a separately programmable clock.
How to Activate the Extended Moonlight Feature
Turn on the HG173.
Select the preferred main lighting channel.
Choose the desired timer duration.
Press and hold the 24Hrs button.
Confirm that the Moon ON indicator illuminates.
The fixture adds approximately three hours of low-intensity moonlight after the main lighting period.
Press and hold the button again to deactivate the extension when required.
Installation and Usage Guidelines
Select the correct model: Choose HG173-19W or HG173-35W according to aquarium size.
Inspect the components: Check the light panel, controller, adapter, mounting bracket, and manual.
Choose the mounting location: Select a stable section of aquarium rim.
Check rim thickness: Ensure the mounting surface is compatible with the one-inch clamp limit.
Prepare the metal bracket: Loosen the mounting hardware as instructed.
Slide the light into the metal clamp: Position the fixture within the mounting assembly.
Insert the metal screw: Secure it in the middle of the designated slot.
Tighten the screw: Hold the light securely without overtightening.
Install the two plastic screws: Secure the light panel to the bracket.
Position the bracket: Attach the mounting assembly to the aquarium rim.
Adjust the fixture: Use the sliding mechanism to position the light.
Check stability: Confirm the fixture cannot slip into the aquarium.
Arrange the electrical cables: Keep connections away from water and salt spray.
Create a drip loop: Prevent water from reaching the electrical outlet.
Connect the DC adapter: Use the supplied power supply.
Turn on the light: Press the power button.
Select a lighting channel: Choose the preferred marine lighting mode.
Adjust brightness: Start with an appropriate intensity.
Set the timer: Choose 3, 6, 9, or 12 hours.
Monitor coral response: Make gradual adjustments when necessary.
Tips for Successful Reef Aquarium Lighting
Start With Moderate Brightness
Avoid immediately using maximum output when introducing a new fixture.
Acclimate Corals Gradually
Sudden changes in lighting can stress photosynthetic corals.
Maintain a Consistent Photoperiod
Regular daily lighting helps create predictable conditions.
Consider PAR Requirements
Coral growth depends on the intensity and quality of light reaching each colony.
Maintain Stable Water Chemistry
Corals also require suitable salinity, alkalinity, calcium, magnesium, temperature, and nutrient levels.
Maintain Appropriate Water Movement
Good circulation helps support coral health and nutrient exchange.
Avoid Excessive Nighttime Illumination
Provide a suitable dark period.
Monitor Coral Condition
Observe polyp extension, coloration, and tissue condition.
Maintenance and Cleaning Guidelines
Disconnect Power
Always unplug the fixture before cleaning.
Allow the Housing to Cool
Wait until the light is cool enough to handle safely.
Clean the Aluminum Housing
Use a soft, dry cloth to remove dust.
Remove Salt Deposits
Carefully clean accessible surfaces without allowing water into electrical components.
Inspect the LED Cover
Remove dust or deposits that could reduce light transmission.
Check the Mounting Bracket
Ensure all mounting screws remain secure.
Inspect the Sliding Track
Confirm that the light remains properly positioned.
Check Electrical Connections
Look for visible cable damage or corrosion.
Keep the Adapter Dry
Do not expose the power adapter or controller to aquarium water.
Avoid Harsh Chemicals
Do not use abrasive cleaners, household detergents, or solvents.
Troubleshooting Guide
Light Does Not Turn On
Check the power outlet.
Confirm the adapter is connected.
Inspect the controller and cable connections.
Lighting Channel Is Incorrect
Press the Menu button to cycle through the four channels.
Brightness Is Too Low
Increase the dimmer setting.
Check the selected lighting channel.
Light Turns Off Earlier Than Expected
Review the 3H, 6H, 9H, or 12H timer setting.
Moonlight Remains On After the Main Cycle
Check whether the Moon ON indicator is active.
Deactivate the additional moonlight period if necessary.
Schedule Changes After Power Loss
Check the timer and lighting settings after electrical power returns.
Light Coverage Is Uneven
Adjust the mounting position.
Evaluate the aquarium's width, depth, and rockwork.
Corals Show Signs of Light Stress
Reduce brightness and review placement.
Corals Receive Insufficient Light
Check aquarium depth and coral positioning.
Consider PAR measurement or additional lighting.
Mounting Bracket Feels Loose
Check the metal and plastic mounting screws.
Confirm that the aquarium rim is compatible.
Important Safety Guidelines
Install the HG173 securely above the aquarium.
Do not submerge the fixture, controller, or adapter.
Keep electrical connections dry.
Avoid exposing the fixture to excessive salt spray.
Disconnect power before cleaning or repositioning.
Allow the housing to cool before handling.
Do not use the fixture with damaged wiring.
Secure the mounting bracket carefully.
Do not overtighten mounting screws against aquarium glass.
Remove the metal and plastic mounting screws before detaching the light from its bracket.
Use only a compatible manufacturer-approved power adapter.
Create a drip loop in electrical cables.
Use an appropriately protected electrical outlet.
Avoid looking directly into the illuminated LEDs, particularly the blue and UV-range components.
Do not attempt unauthorized electrical repairs.
Keep electrical equipment away from children.
Follow the manufacturer's user manual.
Product Specifications
Brand: Hygger
Product Name: Marine One Coral Reef Light
Model Series: HG173
Available Models: HG173-19W and HG173-35W
Product Type: Full-Spectrum Marine Aquarium LED Light
Available Wattages: 19W and 35W
Recommended Aquarium Length: 12–30 Inches, Depending on Model
LED Colors: Blue, Cool White, and UV-Range
UV-Range Wavelength: 395–400 nm
Lighting Channels: Daylight, White & Blue, Blue + UV, and Moonlight
Automatic 24/7 Lighting Cycle: Yes
Sunrise and Sunset-Style Transitions: Yes
Timer Settings: 3H, 6H, 9H, and 12H
Optional Extended Moonlight: Additional 3 Hours
Brightness Adjustment: 10%–100%
Brightness Levels: 10
Power-Failure Memory: Yes
Controller Type: Inline Physical Controller
Smartphone App Control: No
Housing Material: Aluminum Alloy
Light Body Thickness: Approximately 0.6 Inches / 1.5 cm
Mounting Method: Adjustable Metal Clip-On Bracket
Compatible Aquarium Types: Rimmed and Rimless
Maximum Aquarium Rim Thickness: Approximately 1 Inch / 2.54 cm
AC Adapter Input: 100–240V, 50–60Hz
Operating Voltage: DC 24V
Power Cord Sections: Approximately 4.9 ft + 4.9 ft + 1.6 ft
Installation Type: Above-Aquarium
Submersible: No
Primary Applications: Saltwater Aquariums, Soft Coral Tanks, LPS Coral Displays, and Marine Fish Tanks
HG173-19W Specifications
Model: HG173-19W
Power Consumption: 19W
Total LED Quantity: 96
Blue LEDs: 48
Cool White LEDs: 24
UV-Range LEDs: 24
UV Wavelength: 395–400 nm
Recommended Aquarium Length: 12–20 Inches / 30–50 cm
Maximum Manufacturer-Described Light Coverage: 20 × 20 Inches
Light Body Dimensions: Approximately 10.9 × 3.5 × 0.6 Inches
Overall Manufacturer Manual Dimensions Including Mounting Assembly: Approximately 12 × 3.2 × 12 Inches
Operating Voltage: DC 24V
HG173-35W Specifications
Model: HG173-35W
Power Consumption: 35W
Total LED Quantity: 216
Blue LEDs: 96
Cool White LEDs: 48
UV-Range LEDs: 72
UV Wavelength: 395–400 nm
Recommended Aquarium Length: 24–30 Inches / 60–75 cm
Maximum Manufacturer-Described Light Coverage: 30 × 30 Inches
Light Body Dimensions: Approximately 21.3 × 3.5 × 0.6 Inches
Overall Manufacturer Manual Dimensions Including Mounting Assembly: Approximately 24 × 3.2 × 12 Inches
Operating Voltage: DC 24V
Specifications are based on Hygger's official product information and HG173 user manual. The manufacturer publishes both compact light-body dimensions and larger assembled dimensions; these measurements refer to different parts of the installed fixture. Published coverage values describe light spread and do not guarantee uniform PAR or suitability for every coral species.
Package Includes
Each HG173 model includes:
The mounting assembly uses securing screws as described in the installation instructions.
Beautiful, Customizable Lighting for Marine and Reef Aquariums
The Hygger Marine One Coral Reef Light HG173 is an excellent choice for marine aquarium enthusiasts who want vibrant coral illumination, adjustable brightness, and convenient automatic lighting without a complicated control system.
Its marine-oriented combination of blue, cool white, and UV-range LEDs helps enhance coral fluorescence while providing attractive illumination for saltwater fish, live rock, and compatible soft and LPS corals.
With two available wattages, four lighting channels, ten brightness settings, a programmable-duration 24/7 cycle, and optional extended moonlight, the HG173 offers practical flexibility for different marine aquarium displays.
The slim aluminum alloy housing and adjustable metal mounting bracket provide a clean, modern appearance, while the power-failure memory function adds everyday convenience.
Whether you're setting up a nano reef, maintaining a colorful soft coral aquarium, or upgrading the lighting on a medium-sized saltwater display, the HG173 combines marine-focused LED technology with straightforward operation.
Order the Hygger Marine One Coral Reef Light HG173 today and enjoy vivid coral coloration, customizable full-spectrum reef lighting, and convenient automatic day-and-night illumination.
Image 1 of 5
Image 2 of 5
Image 3 of 5
Image 4 of 5
Image 5 of 5
