I have a orange shoulder tang one year old was eating great but one day his face was all sunken in stomach the same way very skinny in24 hours looks bad all over night; black and white clown has one eyeball popping out of its socket cloudy very crazy looking also in 24 hours wats up.
Definitely include info about your setup, filtration, waterchange regmien, do you have a uv that is functioning properly, how many fish in what size tank. Many diseases are able to run rampant in tanks that have less than adequate filtration and maintenance as well as overpopulated ones. Im certainly not positive but the weight loss makes me think it could be uronema. List as many symptoms as possible, that will help narrow it down.