White star polyps not doing well, help!

I bought it about 5 or 6 months ago and it was doing well until about a month ago. Now only maybe a quarter of the polyps open and it looks like the mat is starting to come off the rock.. There is no slime and the color is good, all parameters in the tank are good as well. I have moved it in the last week because I have an aptasia that was very close to it, I thought it might be stinging it, but that doesn't seem to have made a difference. (I am going to get rid of the aptasia soon, my local store didn't have the right stuff to kill it). Any suggestions or ideas or thoughts would be very helpful!

 

You mentioned your params are good, but what are they? Listing them would be helpful. Also, has anything changed in the tank since you added them? What type of flow do you have it in and also what is your placement in the tank? Mid, lower or higher? Maybe a picture would help as well...

 

In addition to your parameters, is there detritus collecting on the mat? Hit it with a powerhead or turkey baste it.

 

When I tested the tank last week everything was good, near ideal params. Couldn't tell you now what they were but I'm going to test it again today. The only difference I've made since getting them was changing from tap to RO water but that should make things better, not worse. There doesn't seem to be any detritus on the mat tho I did notice there are red globe things growing from where some of the polyps should be and there is also a white fuzzy thing growing out of it as well. I'll try to add a pic. The white fuzzy thing is growing in other spots in my tank too, there's a couple on the back wall and I've seen others growing in different spots on the rocks. I also noticed there's an aptasia growing on the underside of the polyp's rock so maybe it's been stinging them.

 

Heres a pic, its the best I could get.

You can see the red stuff growing on the rock, I have no idea what it is. The white fuzzy wouldn't show up clearly, it kind of looks like a tiny urchin shell.

Forgot to mention that the only thing off in the water test was the pH, its 8.2. And also there is a powerhead thats directed at the polyps and its in the top third of the tank, about 6 or 8" below the lights. It was doing well there before, I have no idea why its not doing good now. It used to be full of polyps too, now they're sparse and some are pretty tiny. Chunks of the mat have come off and I catch them floating around my tank on occasion.