Temp and Ph

Jdavison911 · Jan 25, 2019

Have a question for y’all. I set my new system up in our garage (remodeling it) and currently I need no heat as my water temp in 500 gallons is doing a great job at keeping the room comfortable. I fired up a dehumidifier a couple weeks ago to keep things dry. On warmer outside temp days the fish room climbs in temp a little and pushes my tank water to 80-81.0. What I have noticed is my ph goes up as well, 7.9 to 8.1-8.2. Once my fans kick on and the tank gets back to 78.5 the ph drops back as well. So what’s going on? I’m thinking about spending the money on a chiller and running 80 all the times if this is a direct relationship in temp and ph. What’s the thoughts on this? Thanks in advance.

jsker · Jan 25, 2019

I going to let @Randy Holmes-Farley explain this

Randy Holmes-Farley · Jan 26, 2019

There are many possibilities, both direct and indirect. First off, what do you replace evaporation with? It may increase on some days.

Direct issue is that gases (including CO2) are less soluble in water as the temp rises.

Indirect issues are that a great many biological and abiotic processes in the tank speed up or slow down as the temps change. Even air flow through the garage may vary by temp and wind conditions.

Finally, temp also impacts pH measurement devices and calibration should be done at tank water temp, or autocorrected by the measuring system.

Altogether, I’ve not see many reports of pH changing reproducibly with temp.

Jdavison911 · Jan 29, 2019

Thanks Randy. I do top off with kalk water and evaporate about 5 gallons a day, some days a little higher. I didn't think there was really something to it but Ive noticed it to often with this system so just wanted some insight.