I've got a 75 gal planted tank with a bunch of tetras and a couple of angel fish. I wouldn't say it's heavily planted but I do have about 15 plants. Anyway, I'm using an eheim canister filter rated for 80 gallons. No serious worries right now... I'm doing weekely water changes etc. Just wondering if I should consder getting another filter. Should I invest in another canister filter or is it common to get something like a bio-wheel to run along with the eheim?