Planted Tank Guru
Join Date: Dec 2002
Location: Portland Orygun
There is no real way to answer the question. You need enough CO2 to get to 30 ppm. That might be 1 bps for one person and 3 bps for another. There are MANY variables that affect this.
So start out at 1 bps and see what kind of levels you get. Then make adjustments.