What's your ph/kh and calcium /ca it looks like you have some bleached coraline algae. It's popssibly a green coraline algae if you have bright lights but, possibly ,"and sadly more likely,' it's either hair or one of the other problem green algaes. What sort of clean up crew do you have in your tank? Also have you tested ph/kh/ca levels? If they are too low ," coraline algae can use all the calcium in your water," it stops growing.
I'm just going to reply to all of your posts here if that's ok. I'd say that you have an overabundance of nutrients in your water. That's why hair algae is taking over your tank. Nitrates will also cause your anemone to gape like it is and that isn't good unless these guys are eating or pooping they should keep their mouths closed. I know yu say your readings are at all 0 but , from the pics and the c.c. in your tank I don't find that to be very likely. I'd strongly suspect a faulty test kit and would get a 2nd opinion quick. Also if you are having water quality issues it's very important for the continued life of your anemone that you don't correct anything too quickly. The first thing I'd do would be to take my water to a lfs/friend for a second test. I hope that there are no issues and I'm just being a chicken.
That having been said I'd still get rid of the c.c. and go with dsb. Also if your anemone is in c.c. that's part of the reason your anemone isn't happy lta's live in sand not c.c. What kind of lighting do you have and how old is your tank how much lr. do you have. I'm really not trying to flame you just want to answer all of those posts here.
HTH
chris
