Okay, I was just concerned because the size of the bio-media is more than the size of the fish. I know the gph per tank size rule, but does that apply to a 180 gallon tank with 2-3 small fish in it? I've seen a couple members on here have nothing but sponge filters in tanks much more heavily stock (granted they do water changes every day or 2). I clean my sponges every week and they don't have much waste. Not much waste on my sand because I have one Maxi-jet 900 on fan mode at 1000gph, one on powerhead blowing 230gph, and a AC70 powerhead all creating a clockwise whirlpool. I manually vac the small amount of waste every week from the couple places it catches on my driftwood. My ammonia is always 0ppm. I have thought of buying another AC110(for the turn over rate) but the sponges i have now dont really get dirty and bio isnt gonna lower ammonia any more than zero. But there could be a bigger picture I'm missing here. I know most members on this site have a bit more knowledge and experience than me.
Also, ive tried a canister, Had a xp3 in this mix as well, but 2 blue latches broke off of the plastic "latch-holder?" on the base part... now it wont seal, so it poors water everywhere. Also, every time I cleaned it I ended up pouring water all over my carpets and spending 10-20min trying to re-prime it. I've heard of people saying they are much easier but IMO it is a huge hassle that has to be done less frequently.