I will more then likely just keep using the same kind of filter which is one of those tall canister Reptifilters. That's what is placed behind that big flat rock to create the water fall. I will probably buy a new one just because this one is a year old and build the water fall right around the canister instead of just in the front or I may keep it simple and similar to how it is for very easy access if problems arise. I got a couple of river rocks behind the big rock also to help slow down the current it makes and so they don't get there little feet caught in there. They will actually sit behind the waterfall on those rocks and let the little drops of water comeing out the back fall them. There is one that does it more often then the others, must feel good to him.