I believe the only true way to get almost complete CO2 saturation is in-line reactor. I use to have CO2 injected by diffuser and the most I was able to get was 20ppm now that I have reactor I can get 30ppm easy. Currently running 2bps for rate.
what diameter PVC did you use and what is the flow rate going through it?
Okay, so I am pretty sure I'll go with the DIY CO2 reactor. I need a powerhead but dont really know much about them. I looked some stuff on amazon and came with 2 good options. Both of them are made by Aqua Systems. One pumps out 1200gph ($22) and the other 400gph ($16). I'm not sure whats good for a CO2 reactor. Suggestions?
Link to one of them http://www.amazon.com/Aquarium-Systems-Maxi-Jet-Powerhead/dp/B0002567A0/ref=sr_1_4?ie=UTF8&s=home-garden&qid=1258316342&sr=8-4
Btw. I dont know why I couldnt edit my previous post
All based on Rex Grigg DIY Reactor.
2" PVC in-line with Magnum 350. My guess even though the magnum says 350gph I think around the 200gph and Hagen makes a great spray bar.