What's wrong with my GSP?

[2peppers]

I have 2 patches of gsp that have always looked like little patches of grass. But for the last few days they haven't been looking so good. The polyps are not extending much and they don't look as green (more brown now) as they use too. Almost like I haven't watered the lawn for a few weeks. All other corals are looking good (lps, sps, mushrooms) but I can't figure out what's going on with the GSP.

Water parameters are fine. Not ideal but haven't had any major swings. I added a gfo reactor 2 weeks ago to help with phosphates. everything in the tank has responded great so far. The only issue is the GSP. Could the gfo be the cause?

Still pretty new to reef keeping so any help is greatly appreciated. TIA for your help

I will try to post a pic soon

 

[liven learn]

Gfo maybe. Gsp likes nor nutrition in the water. I had both in my tank but seemed to thrive still with gfo. Make sure there isn't any hitchhikers also. Is there brown on the mat?