Zoanthid decline: what's causing my zoas to deteriorate?

[wave_dive]

Hey guys, need some help with my zoas. They used to be fine, but now they're closing up and only the middle section is opening. Had them for 3 months, and I've tried an iodine dip, no nudis on them.

My water params are:
Salinity 1.025
Nitrate 50
Ph 8
Alk 9
Calcium 450

Any ideas why they're not opening like they used to?

[creebo]

Those nitrates are off the charts, and I'm seeing what looks like white blisters or lesions on the sides of your zoas. Honestly, it's got all the hallmarks of pox. Can you get a clearer, closer pic for us?

[fruitymint]

looks like you've also got stars all over the place, and from what i've read, they can irritate or even eat zoas, so that could be part of the issue.

[creebo]

Those look like feather dusters, not zoas to me.

[wave_dive]

Those are sporatoid snails on the gflintix9s, not stars or feather dusters. No spots on the frag itself.

[wave_dive]

Already done an iodine dip, no change

[wave_dive]

Just a quick update, 3 or 4 of them have started opening up again

[bloomie]

High nitrates, been like that all three months? I had a similar issue with mine, new light was the culprit, intensity was too high. Once I dialed it back, they opened up no problem. Also had it happen in a breeding tank, was overfeeding clownfish for spawning, nutrient levels skyrocketed. Not sure if that was the cause, but it's definitely possible.

[wave_dive]

Apologies, those are spirorbid worms, not feather dusters.

[Savoye]

I had a similar issue, and I made a few changes. I bumped up my temp to 78, dropped them to mid rock level, and moved them closer to a powerhead with a pulsing flow. I think the increased flow has helped - debris and amphipods were likely bothering them, and now they've almost fully opened in just a week. That's just my experience, but it seems to have worked for me.