Sudden ph drop 7.4

[Reef-_-Noob]

My PH has been testing over 8.0 for some months now. I tested ph this morning and the api test is showing yellow at 7.4
It has never been yellow. Always purple and blue. Corals are open but I will need to monitor later. Not much I can do right now.
Alk is at 9 calcium seems to be over 500

 

[Reef-_-Noob]

Tested 3 times even in sump all readings 7.4 yellow

 

[Reef-_-Noob]

Is it more likely bad test kit or something with reef chemistry that can do that to ph.

Haven't done a water change in almost a month

 

[Reef-_-Noob]

All corals open

 

[radfly]

Test at same time every day, morning ph will be lower than afternoon ph. Closing windows, or anything that increases room co2 will lower ph.

 

[Reef-_-Noob]

I test in the morning that is why I am concerned never saw this reading

 

[Reef-_-Noob]

It's a sudden drop in ph not just how to fix low ph unless this is the new norm

 

[Garf]

It's a sudden drop in ph not just how to fix low ph unless this is the new norm

If you have an air pump, you can take some water outside and aerate it for an hour or two, then use the api and see what it reads. If it still reads low, the kit is wrong somehow.

 

[arking_mark]

Post in thread 'If you pH is less than 7.8, your pH meter is probably wrong' https://www.reef2reef.com/threads/i...h-meter-is-probably-wrong.862633/post-9413530

 

[Reef-_-Noob]

Hmm so tonight it measured 8.4 will check again tomorrow morning.

 

[Randy Holmes-Farley]

I’d look for a better way to measure pH, or just not measure it at all.

 

[Reef-_-Noob]

This morning it measured 8.2 so strange I do not think it was an accurate reading

 

[radfly]

Get an Apex Jr and stop messing with API. You have wasted two days chasing a ghost... a proper ph monitor should be priority one in reef keeping, following by a proper way to measure alk. (Salifert).