AllPondSolutions 18w UV Light Steriliser for Pond & Aquarium - CUV-118 Fish Tank & Pond Clarifier - Helps Remove Algae and Greenwater

very happy with uv light and good value for money, the quick delivery was excellent and working well, many thanks jq.

Every year I get a problem with a type of algae that grows over everything and so far can find little that touches it, but I also get a problem with single celled green algae that this year literally turned my koi pond into pea soup. I've tried numerous "chemical/biological" treatments and none have worked, these frequently have had mainly five star reviews saying how they have produced crystal clear water yet plainly these have been fake reviews since I've found just like all those who gave them one star that they were useless. So I started looking at UV as a solution and once again I was faced with numerous 5 star reviews stating how good it was and then one star ones saying how useless it was, although I have to say some of these negative reviews weren't necessarily regarding green algae. I was also rather sceptical since my pond filter has a built in UV lamp and that plainly wasn't sorting the issue. Further research showed that my in built lamp was to sterilise the water leaving the filter so obviously wasn't a green algae solution. I decided I needed an extra inline UV lamp before the filter and picked this one since it was close to my flow rate but allowed some wriggle room to make sure it wasn't trying to work on a wrong flow rate. Now this is where it's going to start sounding like a fake review but literally within 24 it really did look like the water was clearing, not a lot but definitely better. Within days it was obviously working and the water was looking clearer! We are now into the third week since I fitted it and the pond is almost clear of the green algae. Do not buy this for anything other than getting rid of green algae, it only has an impact on algae but unfortunately despite it being advertised as this use and this use only some buyers have bought it for brown or other types of water and then given it negative reviews for not working. I only wish I'd taken a before and after picture but I never imagined it would firstly work this quick or secondly work this well. So to repeat if you have a problem with green algae get one of these (make sure you get one suited to your pump) it really really does work!

Read the manual before buying. The Ballast is roughly 1m from the end of the cable, so shortening the cable is not possible. The device draws 29.5W, according to my wattmeter, during testing, and the ballast becomes mildly warm. The unit has its I/O in multiple directions, so do consider where it is to go. The Ballast is also reasonably large. The unit is elementary to put together and didn't leak - good. I will update the review in a week or so and comment on the water clarity. The viewports are useless in a UK summer sun. I will try them again later tonight. The best part by far is the transparent hose tail with the spinning propeller inside, showing water flow. Update 2 weeks later. My small 1000L pond is now crystal clear after being green for years. Fustratingly, I also a month ago improved by mechanical filtering, so this is not a scientific test.

Works well a little nosier than our last one but put a small cloth under to stop vibration 5 stars given

This was a fantastic buy. I have a 3000 ltr pond which was worse than pea soup.I was incredibly skeptical as to it's capabilities. I bought the UV for a 7000 ltr pond. It arrived quickly and it was reasonably priced. It has now been on three weeks .Today as well as seeing my fish ,for the first time in months I can see the bottom of the pond!!!!!! I would recommend cleaning the filter after about two weeks at most. I will clean it again next week and then just do it every 3to 4 months. Ps. I am not a robot !!!

I've had different shapes and sized ponds for 15 years now with a fairly high stock of fish and I've bought 3 of these over the years, they are a great product and last the distance, very easy to change UV bulbs which usually last a couple of years, only reason I had to buy a third one was because the garden flooded and submersed it and blew, that doesn't bother me as it does state that they are waterproof and are not submersible so remember to keep them off the ground. Always had them connected before my filters or before the bio media filter and I've had no algae or bacterial problems for years... It's great for ponds that use water pumps (Gravity fed drain systems are perfect but would still use these in my experience) as the tabulated system inside allows the water to stay in the UV chamber for longer without slowing down the water pressure allowing it to be exposed to the UV for longer to kill parasites and not just little bacteria or algae. With this style UV that has the tabulated system inside i would highly recommend it over just a clarifier. Considering it's a lot cheaper than the likes of an Evo clarifier and at a bigger wattage is a win win, nothing against Evo they are great products but these do the job perfectly for a lower price.

My pond holds 4000 litres I bought this uvc to get rid of the pea green soup which was my pond water where I keep goldfish which I couldn't see anymore the cause was algae I tried well none brands of algae remover but it didn't work after a month of treatment I know it can take up to a month to work successfully THIS ULTRA VIOLET CLARIFIER cleared my pond in 4 days I can now see the bottom of the pond and my beautiful fish friend's Only negative is i never took before and after pictures Highly recommended this product if you have algae problems and also shading the pond helps

I have used All Pond Solutions products for a while however, I have to question the quality of their product construction and replacement components. My dilemma started when I needed to replace the bulb in my PFC 5000 filter and pump combination. I have never had any success with replacing the bulbs previously on other products from All Pond Solutions in the past and have had to replace the unit. I would add that I used to replaced quartz halogen bulbs starting in the 1970’s so handling sensitive, easy to damage bulbs isn’t new to me. Suffice to say I was careful, made sure everything was dry and wore gloves when handling the bulb - it didn’t work and faced with purchasing a new ballast unit as well as the bulb, after determining it was only marginally more expensive to purchase this item and keep the bulb for next year when the bulb will need replacing again. The unit arrived promptly, I assembled it carefully and fitted it into my system. It isn’t complex to install but you do have to be careful to ensure the seals are the right way round and of course clamp the unit onto the pipes securely……that is after you have fitted an 3 pin plug and 3 amp fuse etc. All done, screwed in place and water running through it from the pump - no leaks. Power up the UV light, success the translucent indicator lit up and it worked…….10 minutes later the bulb had extinguished and I was faced with trying to identify the fault. On this occasion I changed the fuse but decided to return it to Amazon for a refund rather than go all the way through the trouble shooting, as it was brand new. 1. i didn’t go through the fault finding process as I see little point in disassembling and reassembling a brand new item which has failed and was obviously faulty. 2. Contacting All Pond Solutions support is a waste of time. They don’t respond if you email them, although I believe that they do respond if you make a negative comment on their Facebook site. 3. This is the third system I have purchased from All Pond Solutions and experience tells me that if the bulb blows, it may not simply that the bulb needs replacing. Changing the bulb has never worked for me and convenience and urgency of need has always resulted in me purchasing a replacement. Once I have received a refund I am going to purchase a replacement unit but I am not confident that it will be All Pond Solutions as they are unreliable and support is poor.