Good afternoon! My green zoas are becoming a paler green, and developing long, thin tentacles. You can see a significant contrast between the attached photos. My tank is about 10 months old. I've got zero nitrates and phosphates. Moderate flow in the area I have this coral. I had a major GHA outbreak and had to dip the rock these guys are on in hydrogen peroxide. It took them about a week to open up again after (and GHA is gone). The other item of note is I started running my 2 AI Primes at only 50% to reduce GHA growth. Any ideas what could cause this change?