I have the Fluval 405 and it works okay. The only problem is I get a burst every now and then of sand on the outtake tube. I've been dealing with this for a long time and the Fluval company said I was the first to have this problem..lol. Can't find where it's gathering in the canister and can't stop it. I do like the chambers for different media. I stick chemi pure and purigen bags in there also. It is a pain to clean but I don't have the room under my tank for a sump. I'm running a cheap Odyssea skimmer and my water has always tested perfect.