we lost then both. Yes it was ICK. We treated the larger clown in an small tank and he seemed to recover overnight - the advice we were given was to put him in a medicated fresh water dose for 1 minute - I could only keep him there for 30 seconds but he did recover for a few hours. He passed this morning and we buried him in our herb patch. We went tonight and purchase 2 replacements for our sons tank and hope we have learnt some valuable lessons - water changes need to be the same temp, PH we need to work out why this drops so quickly, everything else seems ok.