COOSPIDER Aquarium Clean Light Submersible Waterproof Lamp Water Clean Green Algae Clear for Fish Tank Pond 11W (HUV-11)

It cleared my water amazingly! BUT it killed my fish and African dwarf frog. I only put it on for less than 2 days and I even bought a cover separately so the light wasn’t hitting the fish directly because it does say in the paper that comes with it that it can kill fish if it is directly hitting the fish. It kept cleaning my water even after I turned it off. I also think that it wasn’t the only thing that helped because I bought a timer for my light to just have it on exactly 8 hours. I read that having your light on for more than 8 hours can cause that green algae, so that’s why I got the timer.Anyways, u think you should probably take all your fish out of your tank for a couple of days and put them in another container while you have the uv light on and once the water is clear, test your water and make sure the PH levels and everything is good, then put the fish back in your tank. And make sure your tank light is only on for 8 hours. I am not an expert, but I am just telling my experience!

I’m just blown away. This light has been in my 50 gallon Sea Clear for 2 days now and it has been life changing. I tried everything, and I mean everything to get my water clear and nothing else worked. I thought I was going to have to do massive water changes every other day. But now my tank looks like HD. Can’t recommend enough.P.S. This is one of the only reviews I have ever been motivated to leave. I’m that shocked by the results.

Got this UV-C lamp because we were experiencing a bad bacteria bloom in our 15 gallon tank. It had a cloudy/milky white appearance that was enough to cause trouble for the plants not getting enough light. We tried numerous water changes, but it kept coming back right away, so we decided a UV sterilizer was the best way to deal with it. We put this lamp inside an extra hang-on-back filter that we had (a Whisper 30 with the filter media removed; it just barely fit inside) and ran it for approximately 7 hours with the filter at the lowest flow setting. After ~7 hours, the water was already looking much clearer. We removed the lamp and went to bed... The next morning, the canister filter had finished removing all the dead bacteria and the water was now crystal clear! I'd recommend this for anyone wanting to get rid of a bacteria problem quickly. Sorry, didn't think to take before/after photos. Note: this lamp MUST be used in a filter or separate sump/container OUTSIDE of the main part of the aquarium, because it will certainly harm the fish and plants. This is stated clearly in the instruction sheet.Bonus: This lamp can also be used outside of water for general UV-C sterilizing. I used it to solve a problem with a moldy/musty guitar case. BUT, you must be careful when handling the energized lamp! Please wear UV blocking eye protection and take care not to expose it to your skin for any duration longer than a few seconds. It is powerful enough to burn your retinas and prolonged skin exposure may be hazardous. Don't forget, this light kills bacteria, mold and viruses by damaging their DNA with ionizing radiation, and it can do the same thing to you!

I was skeptical but this really did work well. I put it into my HOB filter (Marineland emperor pro 450. I left it on for 5 days straight and it eventually made the water crystal clear. Now that it's clear, I have put it on a timer for 2 hours per day. It doesn't come with a timer so I used a gosund smart plug (also purchased on Amazon) . It's only been a few days since I set it to 2 hours per day but so far the water is still crystal. I'll be buying this again when this one burns out.

This works great. Yes ,it will kill fish and live plants. It warns you all over the package. It must go into your filter canister, make sure the fish can’t see it. I now have crystal clear water. Can’t speak as to how long this thing will last but it seems good quality.

Arrived in a day, package inside brown heavy envelope, light inside store shelf box, with foam around bulb. No damage, worked fine. Sat simply in drain box on back of tank which exposes all water at good rate of flow to UV and away from fish. The 11 watts of light, permanently on for five days, seems to be reducing the algae growth in 90 gallon tank. May put timer on it later, but if this works, what a great cheap solution to the $300 model I was considering. Comes with year warranty, which is what others say is bulb life expectancy, so seems a good buy.

I purchased this because my 120gal take had a really bad algae bloom that I couldn't get rid of. Luckily I have a sump filter so it was no issue putting this in the sump away from the fish...Tank was so green I could not even see through it!for the first 2 days, i didnt see any change with this liston Day 3, it became a little less Greenon Day 4, I was able to faintly see the back of the tank and it was still slightly greensince it started to work on Day 4, I did a 60% water change, and ALL of the green is gone now!This thing really works man!! I tried for a few weeks to do extra water changes to get the algae out but nothing worked.. this light freaking worked! Maybe just give it a few days to start working if you have a big tank because I was worried it wasn't since no changes until day 31 thing though, my acrylic sump has some type of white residue on it where the light is but it comes off when I scrub it so not really sure what it is to be honest

Keep it under water at all times and keep a fan on the power supply otherwise they might burn out quite easily. The 5 i have are doing great but i built a custom power supply case with a cooling fan for my 140 gal reef. UPDATE the lights are starting to give stray voltage to tank 3 out of 5 bad so far less than 3 months in SMH

Our tank was so full of alge. We kept this light on for about 3 weeks and it was crystal-clear! We use it off and on when the alge starts over growing, works great!

I used them for a hob uv diy project (king of diy has a video for it about heaters) and they worked wonderfully. My tank is crystal clear!

The box arrived damaged and I was thinking that the bulb as well. But no, the bulb was okay. I added this UV bulb to my AIO reef tank (20 g) because I had a really bad green algae bloom for days and I couldn't see the fish at all, it was really bad. I added the light to my mini sump, scraped the glass in all the aquarium so all the algae have to go trough the light, did a 20% water change (after few hours) I started all this at 4pm, Feb 19, 2021), the protein skimmer is on 24/7 . On the next morning (Feb 20, 2021) the water is crystal clear ! and skimmer is collecting lots of stuff! I only wish that it comes with a black pvc cover or something sore of plastic, my dividing glass is black but you can still see some light passing through but it's not harmful at all but you see light from a black glass, that is my only comment. I will put it inside of a PVC pipe.

Works very well! Placed it in my pond sump and my water was clear in less than 3 days.Wish i got one sooner!

Took a bit longer to clear the green water. I had to submerge it on the bottom of the tank using rocks, gravel and an old under water gravel filter to clear the water. My Aqua Clear 50 filter just wasn't big enough to completely house the UV light to do the job properly. After 2 weeks the water was just a bit clearer so i tried the latter method which worked because the water cleared within 2 days.