Odd white debris on zoas

[toygrr]

I've had these zoas for about two weeks, they have looked very healthy and have been multiplying. I know the photo is bad, they were fully open before I agitated them. The substance looks like white debris. I brushed some off and basted it before setting it back down. Within 10 minutes all of the polyps opened fully as normal. The other zoa frag I got at the same time is perfectly healthy and from the same tank, they were right next to each other admittedly probably too close to the sand, it also appears sand may have found its way between a couple of the polyps.

Planning on a 30% water change today or tomorrow with RedSea Pro Reef Salt.
Thanks!

Edit: I also had noticed the flow was poor near them and have since moved them and adjusted my pumps. Added photos from a couple of days ago.

params:

Temp - 78 consistently
SG - 1.025
ALK - 12
PH - 7.9
PHOS - .3
CAL - 480
MAG - 1260 (slowly been raising by 30ppm/day for the last week or so)
AMM - 0
Nitrite - 0
Nitrate ~10

 

[TheSheff]

TBH the only thing that stood out to me as far as your parameters go is your alkalinity. Generally I keep mine between 7-9, anything above 10 seems to make corals mad.

 

[toygrr]

TBH the only thing that stood out to me as far as your parameters go is your alkalinity. Generally I keep mine between 7-9, anything above 10 seems to make corals mad.

Yeah and the PH is a little low.. hmm I'll see how they do in the new spot, I'm also gonna get an adjustable guy for the return pump to help with dead spots.

Anyone has experience with these?
https://www.bulkreefsupply.com/red-...8fB2O4eDRtRjoVWhmybYcQ8-cWb80XUQaArB-EALw_wcB

 

[DSC reef]

What you could be seeing are mesenteryial filaments which can appear on all different corals. Reasons range from digesting nearby corals in lps, stress from corals battling for space, feeding responses and chemistry swings.