Scoly shrinking - low mag?

baldislife · 2026-09-13T20:35:08-0400

I have had this scoly in my tank for about three weeks. I feed it an LPS pellet last week and it shrank and hasn't expanded. Color is still good. I tested and my Mag is a little low at 1170. It's already in low flow area. Is it the pellet or maybe the Mag? Thanks in advance.

baldislife · 2026-09-13T20:36:16-0400

Here is a before and after

Mr. Mojo Rising · 2026-09-13T21:47:30-0400

I would say it’s fine, perhaps acclimating still to your tank but it doesn’t look stressed. At this point I see nothing that would make me worry, I would just leave it alone personally and monitor. Good luck.

Fish Fan · 2026-09-13T21:51:35-0400

Mr. Mojo just beat me to my reply, but i would just add that I wouldn't put a lot of stock in that Magnesium test result. R2R staff member Randy Holmes-Farley is a real-deal chemist and a long time reef tank guru, and he advises that home hobby-level test kits for Mag are not reliable. He offers a better solution to maintaining magnesium:
https://www.reef2reef.com/threads/just-say-no-to-magnesium-testing-rmm-is-born.1017528/

Good luck with your Scoly!