I think i might have figured out what the pinkish brown spot was. I remembered that yesterday when I was changing the water my friend went to grab a piece of live rock that looks really corally with lots of holes and pieces hanging off, which is where he normally lives, and anyways my friend grabbed the rock and said he accidentally put a finger on the rectangle trigger and pushed him a bit so, what I though was a disease i think might be a spot where it is swelling where he got pushed against a piece of the rock sticking out. It might also explain why hes hiding as, virtually all injured animals hide while healing. My question is if he is likely to survive or not and also whether or not there is anything I can do to help him. Also when I though it was some kind of disease i bought melafix and pimafix which i am already treating my tank with, which i think ill continue in case it is a disease, and also in case he gets any kind of infection.