Zoas closed melting

[Crotalus]

I couldn't keep Zoas for years, then I suddenly could. They were growing fast enough to sell frags. Now, about 4 months ago, they suddenly closed up and started wasting away. I thought it was the asterina stars. I've removed them all. The only other thing that has changed is the palythoas have slowed down.
I did an ICP test and yes my Phosphates are high. I'm working on that. Iodine was low. Iron was way high. I have ordered a new set of filters and a new DI membrane. That said, my TDS is always zero.
I'm told that Iron isn't attracted to Carbon. Will Puragen help? Can Iron really be the problem?
Nitrate 40
Phosphate .9
Alk 12.1
CA 410
Mg 1350
Thanks.

 

[Drex]

Might be high nitrates man zoos are hard to keep I couldn't keep them ether spent to much money on them so just stop. It could be alot of things like lights, phosphates

 

[murraycamp]

Yes, excess iron and high PO4 could certainly be the culprit. I suggest 2x your water change schedule or volume for the next 3 changes. Purigen isn't a bad idea, but Poly Filter might be a better Fe adsorber. PO4 reduction can occur through various means - GFO being perhaps one of the more effective.

Have you looked for Zoa eating nudibranchs? Many resources out there on how to deal with those.

HTH, IMHO, YMMV, etc.