PH suddenly at 7.0

[cjrudy]

Normally I check my PH every day or too , but I probably haven't checked it in 4-5 days and all of a sudden it's at 7.0 when its normally its 8.2-8.4I run Kalk on a normal basis in my ato and have made no changes recently. The only real changes in the past 4-5 days is that we have shut our windows but a 1.2-1.4 drop is a lotI have checked with both a test kit and hand held monitor and strangely enough the corals look fine currently have nice PE on my SPS
Alk is at 9.0

 

[Timfish]

If your corals are looking good I would take a sample of water and your test kit/probe somewhere to get a 2nd opinion. Did you take a sample of water out imediately after topping off with fresh water? maybe you got a sample that was not mised well.

 

[Kbra]

Water changes a help if its truly low.

 

[Nuocmam]

I have this problem. Been running a CO2 scrubber I got from BRS and it works well.

 

[cjrudy]

Tested again this morning with the PH meter after recalibrating and it still read 7.0Retested with a kit and it showed 8.2. Whew!!!I think what happen last night is in my panic I only added 4 drops instead if 5 with the API kit. Definitely something wrong with my handheld , maybe a bad sensor ?

 

[danka-cedium]

probes only last about 18 months.. dont know if that helps. honestly in my experience, if the corals are happy leave it alone.

 

[cjrudy]

I bought it used from a fellow reefer , probably out if warranty, it's an HM, I'll probably just get a new sensor