Is there a danger in having pH > 8.5?

[ZaneTer]

We are all quite well informed of the dangers surrounding an excessively low pH. What possible problems could we see when reaching a pH of greater than 8.5?

My tank runs between 8.25 and 8.45 on average.

 

[Dr. Reef Verified Sponsor]

as long as the pH is stable in that range there is no negative effect. sudden spike is a different thing.

 

[Randy Holmes-Farley Verified Community Expert]

I think the primary drawback from slight pH elevations (say, 8.4 to 8.65) is accelerated abiotic precipitation. It goes up fast as the pH rises.

 

[ZaneTer]

I remember we touched on this subject before. I don’t get a dkh drop between midnight and 6am. This is despite not dosing during that period.

Does the precipitation occur only at the moment of introduction or is it a process that can occur irrespective of dosing?

Thank you and in advance.

 

[Randy Holmes-Farley Verified Community Expert]

I remember we touched on this subject before. I don’t get a dkh drop between midnight and 6am. This is despite not dosing during that period.

Does the precipitation occur only at the moment of introduction or is it a process that can occur irrespective of dosing?

Thank you and in advance.

Precipitation will happen fastest when alk and pH are highest. That can happen at the point of addition, and during the daytime pH peak.