Thought I would share my tested co2 system. this setup lasts me 3 weeks.
Recipe:
2 cups sugar
1 tablespoon baker yeast
2 tablespoons malasses to have it last longer
items needed:
2 liter bottle, NLS 1mm pellet bottle, 2 backflow preventers, In tank filter, some silicone, & airline.
Tools used, Drill with 1/4" bit sissors.
the setup
the tank side view
the result..
just make sure to check your PH reg. as it will drop adding co2 if you have fish in the tank. I ran it for 3 hours then removed it for 2hours then repeated til the ph stayed the same. Mine dropped from 7.4 to 7-6.9 (color really hard to tell) over the course of the day I put it on. Its now stable.