PH Problem/ Well Maybe
 

Kh 9
Ca 420
Ph 7.6

I have calibrated both of my probes and this is what the result is. When I use my Salifert test kit it comes out at 8.2 I'm scratching my head here WTF. Should I be concerned? I see everyone elses Ph is 8.2. Should I try boosting it up and with what? I don't see anything on the Reef Calculator to do this with.

coral's looking good?

Yes, lots of polyps out but could be a little brighter and there is good growth.

my probe was reading high and my ELOS kit said 8.3 the probe was a year old (they say 2 years is recommended for replacing) so I tried to re calibrate and still high readings i bought a new probe and now its reading what my kit says. I trust the test kit over the probe, but you should be able to read the probe # if your certain about the test kit result )sorta just factor in the difference when you read the probe ) also when you calibrated the probe did you let the calibration # really stabilize - i always find this hard - it likes to keep either falling or raising slowly, i was told to let it calibrate for a while to be certain. hope this helps

Nobody's pH is anything exact. Everyone's pH fluctuates daily. Your's may be just a snapshot of a moment during the day. I would trust your calibrated probes much more than most other tests. Your measurement is a bit low, likely a morning test.

It's 7.5 at lights out and 7.6 during the day. Is it a problem and how do I bring it up without affecting my other water parameters? Thanks

start using kalk for your calcium and alk needs or used baked baking soda for you alk needs. Both will raise your ph.

I have been following this thread as I have the same problem as well. I use "baked" baking soda for kh, but maybe I will try kalk and see if it makes a difference

Dont mess with it ph probes are recommended changing 6 months to a year and much sooner if exposed to air. I would go with the test kit. My probe ready 7.6 and elos test kit reads 8.3.

What's an idea pH for soft coral typically?