I know this is a discus forum but I do keep Clowns as tank mates, the last batch lived 12 years healthily with the discus, albeit the tank is 150 gallons (Imp). Question; out of the blue I found one Clown floating today and the other 3 are acting out of character even for Clowns. The discus are fine as are the other tank mates it's just the Clowns. Water parameters are spot on and there are no visible signs of stress or disease on the fish. Does anybody have specific knowledge about Clowns and suspect anything that may be affecting them?