Why You’ll Love It
Featuring WRGB full-spectrum LEDs, multiple preset modes, DIY scheduling, smart memory, and smooth sunrise-to-moonlight transitions, HG999 auto on-off LED Light is a programmable, multifunctional system that replicates natural light conditions in your aquariums. It enhances fish coloration, promotes plant growth, and supports a healthier aquatic ecosystem for long-term performance in freshwater aquariums of sizes 12–54 inches.
Key Features
Auto On/Off Aquarium Fish Tank Light
hygger 999 LED aquarium lighting uses an IC memory, which has a power-off memory function, and retains your custom program after power outages. After the light resumes work, the fish tank light setting will not be lost. Light cycles run automatically once programmed.
Programmable Design with LCD Monitor
It features programmable, gradual 24-hour light cycle settings with daylight and moonlight. Digital interface with six setting buttons displaying local time, mode, start/end times, color, and brightness.

Note: When the time is up, the light will turn on or off automatically.
Enhanced Waterproof and Heat Management
With its IP68 waterproof build, it is resistant to water splashes and accidental spills. The 1.2mm premium aluminum casing ensures efficient heat dissipation. The fully sealed design safeguards the LED fish tank lights from moisture and water damage, making them safe and energy-efficient for daily use.
Premium LED Aquarium Lighting
Enjoy flicker-free, stable illumination with high-quality WRGB full-spectrum LEDs that are balanced in white, red, green, and blue, enhancing photosynthesis for plants and bringing out vivid fish colors. Lights fade in/out over 15 minutes during day and night changes for stress-free adjustment.

Versatile Metal Brackets for Custom Fit
Its adjustable metal brackets are designed to accommodate various tank sizes of 12″-54″(30-137 cm).
Advanced Programmable Lighting Modes
Day, Night, or DIY mode with up to 8 custom light periods in 24 hours.
1.’53’ DIY Mode:
-Up to 8 programmable time periods across 24 hours.
-Customize brightness (0–100%) and spectrum (WRGB balance) per period.
-Mimic natural seasonal cycles or habitat-specific conditions.
This mode allows for 8 distinct periods (L1-L8) throughout a 24-hour cycle. Each period can be individually programmed with specific start and end times, light colors, and brightness levels to create a personalized lighting schedule that mimics natural conditions. It will automatically display each period’s preset color and brightness settings.
2.’51’ Day Mode:
-Adjustable 10–100% brightness with WRGB spectrum.
-Simulates natural daylight for plant growth and active fish.
-15-minute gradual fade at start and end.
In this mode, the light emits a warm white light, combining red, green, blue, and white (W+R+G+B) LEDs. The transition between on and off states is gradual, taking 15 minutes to ensure a smooth start and end to the day cycle.
3. ’52’ Night Mode:
-Choose from 7 calming moonlight colors (red, orange, yellow, green, cyan, blue, purple).
-Creates gentle illumination without disturbing fish.
-Smooth 15-minute transition when switching.
Night mode offers a choice of 7 colors—red, orange, yellow, green, cyan, blue, or purple. Like the day mode, the light transitions on and off over 15 minutes, providing a gentle shift between day and night.
4. Sunrise & Sunset
-Built-in 15-minute ramp-up and fade-out cycles.
-Prevents stress from sudden light changes.
Note:
1. Brightness adjustment: The intensity of the white light can be adjusted from a soft 10% to a full 100%.
2. Time setting: Both day and night modes can be set according to your tank’s needs.
Usage Tips
1. Setting Local Time:
Use the Up and Down buttons to adjust the local time in hours. Once set, press the gear button to confirm the time.
2. Resetting Local Time:
When ’24H’ is flashing on the display, use the Up and Down buttons to switch between ’12H’ and ’24H’, then press the gear button to confirm your selection.
3. Programming Setup: Press the ‘M’ button to cycle through the modes: ’51’ for Day mode, ’52’ for Night mode, and ’53’ for DIY mode.
Always start at a lower intensity when adding new fish or plants, then increase gradually.
Tips:
- For planted tanks, use higher brightness (70–100%) during Day Mode.
- For community tanks, rely on sunrise/sunset functions to reduce fish stress.
- For a reef-style look (freshwater only), extend the blue spectrum during the night for a moonlight glow.
- You can set Mode 51 and 52 overlap, but it will cause Mode 52 not work.
- Double-check that you disable both the standard daylight and moonlight cycles before setting up DIY mode.
Specification

Package:
1 x LED Light
1 x AC/DC Adapter
2 x Metal Brackets
1 x User manual




























Love this light just wish you would send more instructions on how to program or operate the light. Had to watch a video on how to set and program light and it still doesn’t wanna work on hrs I programed it to. Shuts off hrs before I scheduled it too.
The attached video is a demonstration of how the GlowFish Tetras appear under the HG999 white, red, green, and blue lights. For me, the blue light makes the fish really pop
This morning, I balanced a HG999-18W light on top of a tank’s HOB filter to get the light out of way so it easier to vacuum the gravel. During the process of cleaning the tank, I hit the light, and it fell 46 inches onto the laminate floor. To my surprise, the light is perfectly fine. All of the LED lights still work and none of plastic areas cracked. I did not find anything on the Hygger website indicating the light’s shock resistant rating or what happens if it’s dropped on the floor, but this was a pretty good inadvertent test. However, I do not recommend repeating it.
Light works great. The only issues is, if the power goes out, the timers time disconfigures and wont turn on by itself till you input the time again.
Not my first purchase from Hygger and it definitely won’t be my last as EVERYTHING I have purchased to date have exceeded my expectations. My last purchase was a new led light and couldn’t be happier with it.
I wanted a light that would allow me to dim it while watching tv. This light rocks. You can dim it down in increments to 10%. The fish seem like it too. As always with this company, the delivery was flawless. I’ll definitely do business with them again.