[Lupin]

Hi and welcome aboard.:wave:

On Sunday I noticed that one of his eyes had swollen up and is slightly cloudy. He also has bad conditioned fins, like they are lifeless and the ends look like bits might be falling off.

Sounds like your betta has a pop-eye. What were your water parameters? Wrong water conditions could be the issue here. As for the fins, pics will help. I can't figure out what exactly is happening to the fins?

I have another smaller tank that I can transfer him too, and some ICH liquid - the blue stuff that supposedly killd the organism.

Methylene blue? I wouldn't treat him yet or you might end up treating it with a wrong medication which can be fatal.