It's hard to put a pet down specially when you had it at fry size I had a fh I accidentaly bred with a RD male and a SRT female siblings died and he was the last left then after sometime both parents died then when I went out of the country last Dec he was just healthy and fine my dad took care of him. then when I came back after 3 weeks my dad told me when he came back home the fish was dead I don't know why but well...good luck to your fish.