I'm sorry to hear this.

It's hard to predict an outcome at this point, with the info we have/can get. He could go onto live a normal life. He may have internal or genetic problems that will manifest more as he grows, which could lead to early death.

I would keep him isolated for at least 2 more weeks. If he does not get any worse in that time, we may consider getting him back in the main tank.

~Ash