What is eating up my alkalinity?

blub_blub · 2026-10-14T13:57:33-0400

So far I have a few snails, a pistol shrimp, a yellow watchman goby, and a royal gramma. I thought alkalinity mainly got consumed by corals but I am still seeing a .5-1dkh drop in alkalinity per day. Is this normal? What is causing it to drop so much? Using the Salifert test so readings are within ~0.3 accuracy.

Going on a trip next month and trying to get it sorted with simple care instructions before leaving. Perhaps I need to get a drip system but I’d worry about overdosing it without knowing why it’s dropping so much. Also, I see people add Kalkwasser to their ATO reservoir. Waiting on a better calcium test kit to arrive but if I don’t need to bring up calcium, would adding just the Red Sea alkalinity supplement to the ATO reservoir be an option?

Thanks in advance!

get-salty · 2026-10-14T14:02:32-0400

Are you using an ATO to top off your tank?

blub_blub · 2026-10-14T14:03:10-0400

get-salty said:
Are you using an ATO to top off your tank?

Yes

Mr. Mojo Rising · 2026-10-14T14:27:47-0400

Do you have coraline growing in the tank?

Randy Holmes-Farley · 2026-10-14T14:49:43-0400

Can you post a tank picture?

blub_blub · 2026-10-14T15:14:12-0400

Mr. Mojo Rising said:
Do you have coraline growing in the tank?

There are two tiny purple patches on a snail shell. Then there’s a ton of hard green algae but not sure what type. That developed slowly and evenly, not in patches. Will attach a photo