Baffled by yesterday's test. Low ph????

[adamfrer12]

I am completely scratching my head on this one. My alk in tank is on point, however my ph is crazy low. I've never seen it this low before. Thoughts on why ? This test was done yesterday during lighting hours. I tested it twice cuz I was worried. Here are the parameters. Insight would be great

 

[Randy Holmes-Farley Verified Community Expert]

I'd recheck the calibration. pH 7.5 is possible, but pretty unusual. It would mean a very high level of CO2 in the water and probably your home air.

 

[adamfrer12]

I opened a window to see if that helps

 

[twilliard]

There is a quick way to tell if you have excess co2.
Take some tank water and aerate outside
If there is excess co2 the ph will rise

 

[ryan paggi]

I am having the same problem and I aerated the tank water in a glass with inside air and the ph went up.2. And I think the reasoning behind that is because about two months ago I redesigned my overflows and the piping to my sump to make it quieter so the water wasn't getting aerated as much. Just an idea so I put an air stone in my sump and I will check it tonight to see if it makes a difference

 

[Randy Holmes-Farley Verified Community Expert]

If the indoor aeration test produces a pH rise, then your tank could use more aeration, perhaps for O2 as well as CO2/pH.