Ph/Redox Dropping and corals receding

[miller75]

Over the last couple of weeks my PH and Redox have bee dropping

I use a co2 scrubber and I thought the media must have expired so I changed it but it made no difference.

Everything was looking ok until yesterday but now my corals are sulking, does anyone have any idea what could be going on?

Other parameters are

Nitrate- 20.3
Phosphate - 0.081
Cal - 460
Alk- 10
Mag - 1350
Salinity - 34.5

 

[GT3000XX]

I suspect something has died and is breaking down. Check your ammonia and nitrite. I would suggest a water change as well.

 

[miller75]

I suspect something has died and is breaking down. Check your ammonia and nitrite. I would suggest a water change as well.

All fish are accounted for, I do my water changes on a Saturday so I have got a 20% planned. I have retested and my phosphate was actually 0.03 so that may be why the corals are sulking (They are all Euphyllia).

I still don't understand why my PH and Redox are dropping

 

[Randy Holmes-Farley Verified Community Expert]

I’d try recalibrating the pH meter if you have not changed with dosing or window opening status in your house.

 

[jda]

Even larger co2 scrubbers cannot overcome high co2 levels in your home. My guess is that the ph is dropping as your home is filling up with co2 having the AC running. Do you happen to know the indoor co2 level? Not many do, but there are cheap meters on Amazon, or the like.

 

[GT3000XX]

The redox is still puzzling. My experience has been as the Ph trends downward the redox goes up. How old is your orp probe?

 

[miller75]

I’d try recalibrating the pH meter if you have not changed with dosing or window opening status in your house.

I have just checked the GHL to my Hanna, GHL is 8.04 and Hanna is 7.9. With the tolerances they seem pretty much the same

Even larger co2 scrubbers cannot overcome high co2 levels in your home. My guess is that the ph is dropping as your home is filling up with co2 having the AC running. Do you happen to know the indoor co2 level? Not many do, but there are cheap meters on Amazon, or the like.

I was looking at them yesterday, I think I am going to get one

The redox is still puzzling. My experience has been as the Ph trends downward the redox goes up. How old is your orp probe?

The whole GHL setup is only 2 months old