There are several Do-It-Yourself plans out there for CO2 kits. They're cheap, easy, and work pretty well. It shou;d cost you about 5-10 bucks to do a DIY CO2 kit on your tank. I've used them on most of my tanks and they've worked great. Just go to Google and do a search for 'DIY CO2' and you should find plenty of plans. If not I'll see if I can spell out how to do it for ya here on this forum... *thumbsups