Originally Posted by Mr. Limpet
Nope it out gasses due to little use, just a test and I'd never use a cold water only bib since there's no temp control anyway. I also don't like testing limits/unknows and risk killing my pets
I'm not even sure what you are saying now, lol.
At night, Co2
offgasses by surface turnover/shutting off the co2
injection. Some people like to expedite the process by having an airstone run during the night as well. No matter how you cut it, its a fast change in ph, and not one that poses any serious risk as far as I've seen/read.
I'm not sure what the temp control of the faucet water has to do with testing limits and risking pets.
If the temperature of the water coming out of the faucet is remotely close to that in the tanks, there's no risk, or test, you are just taking unnecessary precautions. And that's totally cool, you can be as super cautious as you feel, but when you start advising others to do so, expect to get called on it.
For some species, breeders actually purposely put in water 10 degrees+ colder into the tank to trigger spawning.