White spots have cleared?

white spots have cleared on my black finned oranda.... however he is now hiding a lot. he is only a lil baby... 2 inches... minus the tail. dont want him to die! i looked closely a him and his tail has white chalk like markings there where as when i got him he was all black... is this from the white spots or is this fin rot setting in? if i change water he gets more active for a bit (1/2hr) then goes behind the plants :( dont want to take the plants out if that makes him feel safer. i have been told by Maidenhead Aquatics not to feed him for 24hrs and see if he gets better. and to keep using the spot cream for another week. o and they checked my water levels and said all was good... but to do 20% water changes every other day until he gets fully recovered. they didnt recommend salt as i said i was wary of killing them by overdoing it. PLEASE HELP :)