Acceptable pH Maximum ?

[SanFranTodd]

I was battling chronic low pH for some time and installed a GEO kalk reactor and now it's been solid 8.3 - 8.4

On a few occasions the pH has climbed to 8.6-8.7 and I shut off the effluent feed until it lowered. What is an acceptable maximum of pH in our reef systems?

[Du]

I think if you don't have visible abiotic precipitation (milk water) when dealing with kalkwasser then you Ph in acceptable range, imho.
More than 9 is dangerous. 8.6-8.7 imho not to bad.

Randy's article about high Ph.

http://reefkeeping.com/issues/2005-03/rhf/index.htm

[SanFranTodd]

when you speak of visible abiotic precipitation are you talking about within the display tank itself (as in milky water floating around inside the tank)?

[Du]

Yes the water becomes milky. Not white, but not clear as before.

[Boomer]

and you may see more deposits on the glass and heater.

This will give you more

What is that Precipitate in My Reef Aquarium?
http://reefkeeping.com/issues/2005-07/rhf/index.htm

[Randy Holmes-Farley]

That pH (8.7) sounds too high to me, and the white precipitate is evidence that it is too high. Is it otherwise hurting organisms at that pH? I'm not sure.