CichlidFish.com - Fish That Think.

or does it have more bacteria area

thats most of the advantage of a canister is more media area for bacteria to colonize and the different grades of media all in one unit.

Other wise they polish water better then hang on's,but if your water's clear and parameters are good I don't think they're worth the extra cash. I mean I'd take 2 ac500's over most canisters at the same price anyday, but thats just my oponion

Powerheads can also be used as a pump (with or without the sponge prefilter) to push water to an external filter like a wet/dry or trickle filter.

I think Fish Novice's trickle filter is probally something similar to mine (if not correct me) - powerhead pushes water up a tube into a box on top of the tank then gravity pulls the water through the filter box and the media then it goes back into the tank.

sheet of floss??

you can buy just the floss like filter inserts are made out of around here it's pretty cheap,like $4-6 for a 2X2 sheet

BUT ive heard stories about wisper being a bad polisher..., and people say that penguin/emporer is better....this, i think is because the filter cart is very thin

the filter inserts on both are the same thickness if you buy any aftermarket or bulk replacements some even interchange.On the brand name replacements a whisper should be a better cartridge for two reasons 1) you can leave out the carbon since you build your own whisper brand cartridges 2) some of the penguin/emperor cartridges only have floss on one side. also on the whisper brand replacements they're actually alot thicker if you count the fins inside the frame but it's just empty space so it shouldn't matter - Both a good filters,just different people will probally have different feelings about both, I have both and like both but unfortuneatly the new whispers are going downhill

one additional point,if your trying to make a hang-on filter "polish" better change the size of the media! example - if a ac 500 doesn't polish good enough for you ditch the sponge and go with a small pore sponge! simple! easy and cheap!:D The "stock" ac500 sponge has pores alot bigger then the openings in floss but a small pore or closed cell sponge has smaller openings then floss.Take the simple easy route instead of the pay double for the same thing aproach