New Zoa not looking the best :/

Mike1995 · Oct 14, 2018

I got a second Coral frag, some sort of zoa a few days ago. My first one is doing really well and is always wide open. The new one is on a piece of rock, there's several larger polyps and several smaller ones all over it. The rock is about 3 or 4" in size. I've noticed some of the polyps open, but 3/4 of them are not. There's some kind of green algea looking stuff growing on the rock and on the polyps... Does anyone know what exactly is happening? Will the coral eventually open up? My other one was open and happy like the next morning after I got it. I'm still knew to corals so any advice is appreciated.

My tank is 75g.
Ammonia, nitrite both 0.
Nitrates 5~
Phosphate .04
Temp 81/82
Salinity 1.024
pH 8.2

biophilia · Oct 14, 2018

Zoanthid polyps will sometimes close up for a few days. Especially if they're stressed or being aggravated by algae growing around their base/tissue. If you can, try to blow as much algae off as possible with a turkey baster and then just leave them be for a few days. If for whatever reason they're still closed in 3 or 4 days or show signs of fungus or spots, there are some more aggressive things you can do (like dipping them and the attached rock in a container of 9 parts tank water 1 part household hydrogen peroxide for about 5 minutes and then rinsing off well before placing back in the tank). Your water parameters look good, so I'm sure they'll come around and open up soon on their own though. Good luck!