GSP, not all polyps opening up

[krak256]

For some reason, my green star polyps aren't all opening up. I noticed that some stems have brown growth around them and then I spotted another patch that had black jelly like substance.

What is this? What do I do?

 

[marki24]

what are your water parameters? how long do you have it? is it a new coral to your tank?

 

[krak256]

i've had it for over 2 months now. my water parameters are all good, except for a bit of nitrate which i'm trying to solve with a fuge.

have you ever encountered a brown film/black fungus(jelly)?

 

[ecvernon]

maybe algae, diatoms, cyano bacteria... if you have nitrates and phosphates thats what it could be. i have a algae problem in my tank and if i did not remove some of the growth off the coral they would not open