diseases

hi all I have 8 euphyllia torches and one of them starting to have there black stuff in their tips and comes down to the t, and others are literally turning black. anyone know what is this and how to deal with? Ca 430 Kh 8 po4 0.03 no3 25 Mag 1320 Salinity 35 Ph 8 Thank you

Hello does anyone know what is the black thing on my coral?

My tangs are itching like crazy and are starting to get blotchy. I stopped feeding nori for a couple weeks to try to encourage them to eat off of the rocks however I just started them back on it a few days ago. Can anyone tell me what my problem is? My house was also just painted a few days ago...