Zoas are disappearing

[rconnew]

Suddenly my Zoas are disappearing and Xenia appearing. When I first put them in they were fine then one day I did a water change and the closed up and stayed that way for a while. They are coming back out now but many appear to died? Where that has happened I now have what I think are Xenia in bit grey and orange colours. Dipped and checked for unwanted guests and never found any. Anyone any ideas what just happened please?

As they were when I first bough them and as they are now.
Ammonia 0
Nitrite 0
Nitrate 0.10
Mushrooms, Star polyps, Xenia all doing well only Zoas not looking good.


Thanks

Richard

 

[slgcmg]

What's you phosphates at. Looks like your having an algae bloom

 

[SLOreefer805]

What types of fish or inverts do you currently have in there?

 

[SIR PATRICK]

Looks like algea is smothering out your polyps to me