Wow thanks J! I had added new T5 lights. And also my calcium dropped below 300 oops! Lesson learned. So I think I stressed the SPS a little or gave them 2nd degree burns with the new lights. I turned them down after I noticed the loose skin and slowly dosed up the calcium to normal. I still see some of the larger blisters but from what I read online if will slowly get better as long as the problem is fixed.