The Kessil A500X is a high-intensity 185W LED fixture designed to deliver the power, coverage, and deep penetration of a metal halide light without the associated heat or high energy consumption. Utilizing Kessil's signature dense matrix LED array and specialized optics, it provides brilliant, uniform light coverage with exceptional color blending and a beautiful shimmer effect. With Kessil Logic, the light automatically maintains a balanced, optimal spectrum for coral growth and coloration as you adjust the color, simplifying the tuning process for your reef aquarium.
This powerful fixture is engineered for performance, providing a high photon volume density ideal for demanding coral systems. It offers a recommended coverage area of 36 by 36 inches, making it suitable for larger tanks. The beam can be precisely shaped using the included 55-degree reflector or narrowed further with an optional 35-degree reflector for even deeper penetration. Control is versatile, with onboard manual controls and options for advanced programming via the optional WiFi Dongle or Spectral Controller X for smart communication and seamless integration.
Specifically created for the experienced SPS coral aquarist, the A500X meets the rigorous lighting demands of large, SPS-dominated reef systems. Its ability to deliver intense, properly-tuned light is essential for achieving optimal growth, vibrant coloration, and long-term health in the most light-demanding coral species. If you are looking to cultivate a thriving SPS reef with professional-grade lighting, the A500X provides the necessary power and sophisticated control to succeed.
| SKU | 232123 |
| Color | Black |
| Category | Fixtures |
| Features | Boost Fluorescence, Dimmable, Energy Efficient |
| Warranty | 12 months |
| Application | Reef/Coral Growth |
| Control Type | WiFi (with optional controller), Digital DC Control (with optional controller), Onboard Controls |
| Aquarium Type | Saltwater |
| Fixture Style | Puck / Pendant |
| Lighting Type | LED |
| Optional Mounts | Mounting Arm |
| Power Consumption | 185W |
| Power Cord Length | 10 Feet |
| Max. Light Coverage (Width) | 36 in. |
| Max. Light Coverage (Length) | 36 in. |
I bought a pair of these for my tank. They provide excellent light, and with the various lens options are able to get some good depth penetration. One light started acting up and shutting off intermittently after about 18 months. It seems the cooling fan is shutting off for no reason and then it shuts off due to (I'm guessing) overheating protection. It will turn back on after leaving it unplugged for a bit, and if the fan comes back on, it will stay running, but there is no guarantee to how long it will stay on. I love the lights, but am extremely disappointed with the (IMO) short lifespan for the cost. I'll probably end up replacing the fan on the light, but this can't be done without ruining the waterproofing.
I got rid of 3 radion gen 4 pro with 2-T5 and added 3 of these over a 150 keeping the T-5. The results are amazing. I am getting better color from my SPS, with better par. After having these I am done with Ecotech.
The A500X is a awesome light for SPS aquariums. I am using a single fixture over a 60 gallon cube and have no problem keeping SPS coral throughout the tank. I even keep a few clams at the sand bed that have shown plenty of growth already in just a few short months. I like how easy it is to dial in the color of the light from blue to white. I found the Violet channel can bring out more fluorescent pop of your corals. I use it at 60% with my Color set to 30%. This light is very bright so you will want to dial in the intensity with a PAR meter if you have access to one.
This light is by far the best light I've ever tried for my SPS corals. You can practically mount this thing on the ceiling with no issues! Granted you might need the 35 degree reflector for that higher mounting level but still. I haven't gotten better results from any other brands. My SPS thanks Kessil for their wonderful product! Staying true to Kessil no matter what!
I picked up 3 of these to replace 250W DE halides on magnetic ballasts (more like a 300-350w output) and can't be happier. I used our clubs Par meter to take before and after measurements at 30 points around the tank and these lights can meet or exceed the halide Par levels at most measurement spots around my 24X72X30 210 mixed reef. I mounted them a little lower than the recommended height to limit light spill out of the tank and didn't have too terrible hot spotting. Kessil really should have a reflector to allow 9" height (to even out the par) and redirect all the light down into a 24"X24" square which is a very common installation. The output and color of these lights is really impressive. I added purple and red in the amounts recommended by BRS and my fish really pop but the tank doesn't look odd at all. I ended up at a color setting of 60 as opposed to the 30 recommended by BRS. 30 is just way too blue for me. 60 pretty much matches the Phoenix 14k with actinc T5 I used to run. I really suggest borrowing/renting a Par meter when you swap these in. I found the visual difference between 70% and 100% power is not that much but it makes a huge Par change. Overall, VERY happy with these lights so far.
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Kessil A500X Controllable LED Aquarium Light - Tuna Blue
by Kessil
Lighting
Reference reading: Marine invertebrates on Codexery
Species guides on Codexery
- Duncan coral — Scientific name: Duncanopsammia axifuga · Maximum size: Polyp diameter 2–3 cm; corallite diameter 10–14 mm source
- Torch coral — Scientific name: Euphyllia glabrescens · Family: Euphylliidae source
2 retailers · 2 in stock
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19% off A500X Controllable LED Aquarium Light - Tuna Blue
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