well i have been thinking about getting a canister filter for a new tank and have heard good things about fluval my question is i see a 404 and a 405 but i dont see a big diffrence between the 2 other then about 60 bucks in price. If i go with the 404 is it going to be sufficent for a 75gal heavlyplanted tank or should I be looking for something else? any advice or comments would be appreciated.