Unhappy green open brain

[awestruck]

I have a red "meat coral" (looks very much like an open brain) and a neon green open brain. The meat coral is high up a rock and is growing by the day and always has its tentacles out at night. The green brain sits on the sand bed and only puts out a few, short tentacles at night. Today I looked at it and there is about 1/5" recession (not 1/5 of the coral, just about 1/5 of an inch). I absolutely cannot understand what is wrong with the open brain. And, every other coral in my tank is doing very well. Any thoughts...?

[Rockitmakr]

Perhapps lighting. Or, is anything nipping at it?

[raoul]

Ours did that recently because we messed around with things by adding a sump. We also had to be careful with how the flow was hitting it. It doesn't like direct/heavy flow - at least ours doesn't.

Don't know if that helps or not, but good luck anyway!

[spsgtr]

definately does not like high flow becasue it may tear the flesh. you can try feeding it if there are small tentacles. good luck

[awestruck]

Thanx everyone. Guess what---I moved it over in the tank, on the bed, out of a swirling flow and it looks better already. Poor thing was getting blasted. What's kinda weird is that one of the power heads shifted a little bit which changed the water flow. Unfortunately, the ph is hidden behind rock and I just didn't notice that the flow had changed its direction. Thank you for helping and have a great week!