Half Zoa colony closed

[SudzFD]

Hi guys,

I have two zoa colonies in my tank. A red one, I have up high and a green one I had down low. I started to notice the green one the top half was staying closed all the time. I think my crabs were walking in it, or my sand goby was dripping sand on it. I moved it up out of the sand goby’s path but it’s still half closed. I’m Wondering what everyone’s thoughts are. My fish are great and my bubble tip and red zoa colony is great. Xenia seems happy.

I dose Salifert All in one once a week and Fluval iodine once a week.

35g tank- live sand mixed rock, protein skimmer working well and hob filter with Nitra zorb, charcoal, poly filter and bio wheels.

Ammonia 0
Nitrite 0
Nitrate 10
Ph 8.0
Calcium Carbonate 425mg/l
Phosphate .25 ppm
Alkalinity 120 mg/l (7dkh) a bit low I think.
Carbonate 180 mg/l

I have my peak lights (white and blues on 6 hrs per day)

Blue leds for 11 hours.

Light specs in photo below (36” size)

 

[Coral Reef Keepers]

Any algae growth on them? Take a turkey baster and blow some water around on them and see if anything comes off...

 

[SudzFD]

So, I noticed two things:

First I blew all my zoa colonies off with turkey Baster . These closed green ones were much dirtier than the rest, so I think this should help.

Second:

When I placed these zoas in my tank, a small piece with four polyps fell off and I stuck it in a shady spot mid tank. Those are doing well. Then I see it’s the “light” side of the zoas that are closed and the more indirect side is open. So maybe these zoas like a little less light. I moved them to a lower spot in my tank and will watch them and keep them clean and see if there is improvement.