When ph is rising?

I have a central ac but its only on for about 4 months of the year. We live in Maine so its a cooler climate. We have the windows open. The room was built around the tank so I designed the tank out of sun and to have plenty of ventalation. This is just weird after 2 years it shifted. I just figured that maybe something was depleting like cal or mag. kh is 12. and that is what its been forever. I do test and dose and perform monthly water changes. I change 50 gallons that is about 20 percent 1 time a month if I need to i dose in the middle of it. I just figures this was strange.

 

no idea other than what was stated. new test kit maybe.

 

be honest with ya, if all your major parms are stable and ph is 7.9-8.4 dont worry about it. nice size tank! its 4 of mine put together.. mini-jacuzzi

 

LOL k just for the laugh! I was not to worried yet just thinking what is up with a change over the last year.

 

Did you lose or trade-in a large fish. Their respiration produces the majority of the CO2 in a tank.

 

I lost my male crosshatch it was about 9 in long other then that its the same tank just one exp fish down...