My pH controller read my pH to be 6.1. The only thing i did different since yesterday was put in new driftwood and started injecting some co2 from a pressurized canister this morning. The pH test kit reads 7.3 but the pH controller reads 6.2. What do you think is going on? i just recalibrated the pH controller twice and things seem to be working fine. I really need help! The water is around 84 degrees... what do i do to make it go back up and normalize it? water change perhaps?