I have a 20 gal tall aquarium with 6 pork chop fish and 6 neon tetra, I have pothos growing out of the top of the tank. It has a canister filter with just k1 filter media and then I have a 50 micron house filter attached. And a small filter inside I liked to have ready if I got new fish or set up a new tank. I have a box with 46 ish filters left in it