Your right Matt I haven't hooked my reactor up yet. I have been thinking hard lately about CO2 and how best to get it the water. I am thinking about buying a canister this weekend but having the reactor outside of the tank does freak me out a little. Thats a lot of water if something gives way. I am also thinking about the ceramic/glass diffusors from Japan. I have a cheap version in my 55 and it does a reasonable job. I am also thinking about building a power head/tube with sponge type, but I just don't know which way to go. It's driving me crazy.