I've been thinking about building an external CO2 reactor just to get the equipment out of my tank and to increase efficiency. The problem is, I haven't seen many external reactors powered by powerheads.
Gravel cleaners are basically 3 parts, the wide tube, the thin tube, and the non-clear part connecting the two, you might call it an adapter. Well, I have an extra gravel cleaner that I could use this adapter from. I was thinking I would put bio-balls in the tube, tightly put these adapters (they are green for me) on both ends, and possibly seal them with silicon. Then I would drill a hole towards the middle-top of the clear tube and run the CO2 tube through it. I would silicone seal this. So this is the main reactor. Then, I would use the thin tubing to run it to the reactor (from the powerhead) and from the reactor (back into the tank). I would probably silicon seal the connectios just to make sure.
Do you think this would work? The powerhead is a Rio 600, which works fine now. Thanks for any replies!