Daily PH Swing

[ItsAName]

Curious if this is normal and ok?

I have a refugium with sea lettuce, chaeto, and mangrooves. Its got one of those purple kessil lights that turn on at night. My ph meter is in the refugium.

During the day the ph reads 7.6 to 7.7, when the light kicks on at night, the ph raises to 8.2 and goes back down when the light is off.

Is such a large ph swing bad for coral? Should I even care

 

[Randy Holmes-Farley Verified Community Expert]

It is normal to swing, but your low end is lower than I'd like to see, since aragonite (e.g., coral skeletons) may begin to very slowly dissolve at pH 7.6.

I discuss pH issues here:

pH And The Reef Aquarium
http://www.reefedition.com/ph-and-the-reef-aquarium/

 

[ItsAName]

It is normal to swing, but your low end is lower than I'd like to see, since aragonite (e.g., coral skeletons) may begin to very slowly dissolve at pH 7.6.

I discuss pH issues here:

pH And The Reef Aquarium
http://www.reefedition.com/ph-and-the-reef-aquarium/

Thank you for linking the article! I'm sure you don't need any anecdotal evidence, but based on your comment about 7.6 being too low I went out and got a CO2 Scrubber. Hooked it up, and in the first day the PH has been stable around 8.05 (during the day) and 8.15 (at night). It's been this way for about a week now. I expect to see the coral double in size every 5 days now haha

 

[Randy Holmes-Farley Verified Community Expert]

Thank you for linking the article! I'm sure you don't need any anecdotal evidence, but based on your comment about 7.6 being too low I went out and got a CO2 Scrubber. Hooked it up, and in the first day the PH has been stable around 8.05 (during the day) and 8.15 (at night). It's been this way for about a week now. I expect to see the coral double in size every 5 days now haha

Maybe they will.