I have no idea what happened to him

When he started failing it went really quickly and then he died within a few hours. Looking back I guess the signs were there, he basked an awful lot... I thought it was just a baby thing. He was SO young and SO small. He did swim but not as much as Stelo.
It seems it was just a failure to thrive situation

I don't think there was anything more we could have given him. We gave him the best environment we could.
Stelo seems fine so far. He has always been stronger than Cupid was. He eats like a pig, swims and chases the fish and really seems to be thriving. I'm scared to death now though, that something is going to happen to him too. I don't think I could take losing them both.