Is nightime the right time for CO2?
I am just so confused.
I am being encouraged on the one side (by no less a person than Tom Barr) to run an airstone in my tank at night to keep up the O2 levels when the plants quit contributing.
My LFS guy (Dan at HAW, Houstonites, myself included, really respect his opinion) says I should run my CO2 all night because it takes so long for the CO2 to diffuse all thru the tank in the morning when the lights come on.
Of course, there is not a lot of point in adding CO2 if you are just going to drive it off by agitating the water with an air stone. (Okay O2 does not drive out CO2, but an airstone does drive it out, just by agitating the water).
I am thinking about about changing my "manual" pressurized CO2 system into an "automatic" one (though I am worried about keeping the pH controller calibrated, a topic for another thread), but I think if you tried to maintain a constant pH with an airstone running you are going to run thru an awful lot of gas.
What is the best schedule for airstones, lights, and CO2?
What if I were to turn the the airstone on and the CO2 off when the lights went off, then turn the airstone off and the CO2 on, 4 or 5 hours before the lights come on?
I would be vulnerable to low oxygen levels just before lights on, but if I time it right I should be able to have some CO2 built up by the time the plants need it but still have some oxygen left in the tank.
Does anybody use a schedule like this?