I wrote an article recently for my local fish society's newsletter on my use of a paintball CO2 cylinder to inject CO2 into my 5g tank. I figured ya'll might be interested in this as well.
http://www.derekparr.com/minico2/
I should note though.. that the way I did it is probably quite unsafe since I was trying to keep the price down and I wanted to keep the dimensions of the apparatus to a minimum. So.. people should do as I say, not as I do... at any rate if anything goes wrong for someone else.. its not my fault. I'm comfortable with the risk, but I'm not going to blame anyone else for something I did, regardless of where I may have or have not read it.
http://www.derekparr.com/minico2/
I should note though.. that the way I did it is probably quite unsafe since I was trying to keep the price down and I wanted to keep the dimensions of the apparatus to a minimum. So.. people should do as I say, not as I do... at any rate if anything goes wrong for someone else.. its not my fault. I'm comfortable with the risk, but I'm not going to blame anyone else for something I did, regardless of where I may have or have not read it.