ph concerns

[SwiftStorm]

Hi, I'm starting a 20 gallon build and doing an extended leak and equipment test while I slowly remove pieces from a larger tank. I filled the 20 with only RO water and have got the hydros mostly all programmed. My ph probe was initially around 7, but now is going from 7.1 to 7.2 during the day. Maybe an occasional spike at 7.3. How can this be? I have zero rock or gravel in the tank, and my radion only runs for about 30 minutes at night.

Thanks

 

[Randy Holmes-Farley]

Hi, I'm starting a 20 gallon build and doing an extended leak and equipment test while I slowly remove pieces from a larger tank. I filled the 20 with only RO water and have got the hydros mostly all programmed. My ph probe was initially around 7, but now is going from 7.1 to 7.2 during the day. Maybe an occasional spike at 7.3. How can this be? I have zero rock or gravel in the tank, and my radion only runs for about 30 minutes at night.

Thanks

If this is fresh water for testing, pH measurement is not useful.

 

[SwiftStorm]

It will be a saltwater tank. I have just been letting everything run and didn't want to waste the salt for this test.

 

[Randy Holmes-Farley]

It will be a saltwater tank. I have just been letting everything run and didn't want to waste the salt for this test.

Yes, that's fine, but measuring pH in it isn't telling you anything useful for when salt water is in it.