Me, earlier: "when temps get higher they cannot absorb as much co2...it is a fine balance"
Let me rephrase--"When temps get TOO high, they cannot absorb as much co2" this is bc now the open pores want to close up to prevent too much water loss and also have to try harder to respirate and cool instead, of absorb co2, --BUT when there is abundant co2 and temps are good--the pores only open a little to absorb the good stuff--and won't lose as much water as when they have to open wide to find the co2...also why they can also endure higher temps..they are naturally evaporating less water
but yes--you can use co2 and exhaust--just cycle them--you don't want to waste that gas...