Review on 🐠 Optimized Fluval U Series Underwater Filter for Aquariums by Denise Harris

I have a planted 40 gallon Lang (48 x 13 x 17) and needed to replace an old Fluval 202 canister filter. Really didn't want a new canister filter and the bio wheel didn't work for me because of the plants. There are HOB filters that would work, but in my experience they are just as clumsy and difficult to clean as a full canister. So the U3 seemed like the perfect compromise; No filling, no hoses, just dip and go! This filter is very easy to clean and maintain. I like the central "spray bar" between the two main outlets. The flow adjustment knob makes it easy to find the perfect balance between the three outputs, a very smart and useful feature. I also appreciate that the trays are oriented vertically, no need to stack or dig trays. My only criticism of the U3 is that it's quite small for the work it claims to do. It claims to be good for up to 40 gallons, but in truth, 40 gallons might be too much for this filter. I believe if you had an aquarium with no plants and a minimum population, everything would be fine. But most people might want to consider a move to U4. I'm considering buying a second U3 myself. The outlet is powerful enough to provide all the circulation I need which means I can take my powerheads off. They fit into the corners of the tank so well that I should end up with a really nice clean look. I also think that even two of these small submersible filters are easier to clean and maintain than one large canister filter.