> From: Edziu Iskra <edziu at gate_cybernex.net> > Date: Fri, 6 Dec 1996 11:14:41 -0500 (EST) > > My question is this: what is the fluctuation in CO2 levels relative to > the natural level of CO2 in well-aerated freshwater? I think "The Optimum Aquarium" book has some tables that show this. However, since our systems have a much, much larger plants and fish to water ratio, the cycling we see is very atypical. George