Planted Tank Guru
Join Date: Sep 2004
Location: Garden City, KS
You never told us what CO2 recipe you're using, nor how you are diffusing it into the water, nor how much surface turbulence there is... these things are important to know, if we are to suggest you change your methods.
First off, that's a big tank to be using diy CO2 on. I realize you have 3 bottles, but still, the tank holds a large volume of water that needs to be pumped full of CO2, and at best a diy recipe is only going to give you about 1-2 bubbles per second. Secondly, the recipe you are using has a lot to do with it... what if you just made the recipe wrong? Also, what are the ambient room temps? If it's too cold, the yeast might not have the appetite they would have at warmer temps, leaving you with less CO2 as a result. Also, provided the recipe is good, and you are diffusing it properly, you could still off-gas the CO2 by creating too much surface turbulence.
Lastly, do you have a drop checker? Without one, you are pretty much just guessing at the concentration of CO2 in the water. Every CO2'd aquarium needs one, IMO.