Acros fully retracted before light cycle ends

[Matt Bravo]

Hello everyone, I need some help with my acros.

As the lights go on, they look great. Polyps are out and they look healthy. Now as soon as lights start turning off all polyps retract fully. This has happened twice already in the last week but all my other corals look healthy

420 calc
9.0 alk
Mag 1400
7 nitrates
.13 phosphates
1.026 salinity

I’m mainly worried because I just bought a few pieces today. I went out after putting them in and when I came back one of the 3 new ones completely RTN on me. The others haven’t peeled yet, one shows no polyp extension and the other is showing some. I’ll add a few pics below too

 

[Matt Bravo]

I just realized one of my other acros has a bit of skeleton showing too, note that they were recently fragged before purchasing too. Also note that I did see a sexy shrimp on the coral in iodine dip and I saw an emerald crab on top of a monti the other day too.

Could this be invert related or is it more likely water quality related?

 

[Matt Bravo]

bump