it's doing a good job in my bare-bottom 75g.....only reason there's anything on the bottom is cuz the tank is too short for the intake-extension. Also has a Lee's Triple-flow corner sponge filter in it. Does the Aqua-Clear come with designated cases made specifically just for carbon so u can pour your own and sub with generic filter pad to avoid buying expensive cartridges every 2-4 weeks ?.....and slots for up to 4 of those expensive cartridges if you choose? The outflow creates a current 4 feet and only stop cuz the tank does, I 'm sure it could reach the other side of a 6 foot tank as well.