I have a rock in my tank I bought with 5 Xenias on it. There are 2 new ones now, they're tiny. Out of the ones that came on it, they all looked the same except for the one in the middle. It was darker colored and was taller than the rest. I had a bit of a sand storm in my tank about a week or 2 ago. I gently picked up the rock that the Xenia's are on and turned it upside down to let the sand fall off, and sit it back down where it was. Since then, the darker Xenia hasn't been looking too good and today it is completely shriveled down as low as I imagine it can go. The other Xenia's still appear to be thriving. As it is all shriveled up, I assume it it dead. The others are a light peach color. This one was more of a light purple and now its a dark purplish blue. It is on a small flat rock between the other Xenias. Should I attempt to remove it from the tank?