allpondsolutions 36w UV Light Steriliser for Pond & Aquarium - CUV-136 Fish Tank & Pond Clarifier - Helps Remove Algae and Greenwater

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.

Care to replace works well needs care to fix

Liked the design, integrated transformer, various connection options and a clear band round the middle to show when the lamps on. Only downside is the lack of hose clamps and cost, but you get what you pay for.

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!

Had a Jebao 18w and this is similar comstruction and design, with improvements. The removal of the UV tube and crystal cylindar is easier, the install of the UV assembly has a nice slip ring fixing so not screwing cable every time like the Jebao. The ballast is a lot more moisture resistant and complete sealed unit . .so all good. as it uses the same UV lamps and yhe quality of the crystal tube is same should perform the same, but hopefully longer before it starts blowing lamps like the Jebao.one critique is the hose fittings are a little small diameter for pipe and need a good quality ring clip to keep from leaking at hose connections, they just fall off and dont have the deep barb's . . but installed with no leaks now I wait to see tesults.Very happy with the price, same lamp size so will be replacing the other two UV's if all goes well.

My garden fish-pond had a severe attack of "green-water" (mainly blanket weed growth) following the winter, and the water had become nearly opaque. After fitting this steriliser in front of, and in series with, the pond filter system, the water was virtually clear within a week. I can now see the fish clearly right down to more than a metre below the surface. A very effective device. It's advisable, of course, to choose a model that's capable of dealing with the particular pond size it's used for. The UV light has the effect of killing and coagulating the blanket weed spores and cells.

Great item and great price. The pond water is crystal clear now.Thanks