I've been using my sunsun 403b (2000l/h) on my 66 gallon for about 9 months now, only had to clean it three times, and it keeps the water relatively clean. I'm planning on setting up a 180/220 gallon some time this year and I'm probably going to filter it with a sunsun, the uv model though, along with a sump. I've owned fluvel and Eheim canisters before, and the sunsun is really a bargain in terms of bang per buck. I want to try and set up the cfs 500 on my 40 breeder that I have in storage right now.