He's done this before and healed in his own tank. It's never been this bad, granted, but I think he'll do okay. Actually, if you look at my avatar pic you can see at the top of his tail where there's clear tail in between patches of red? He's torn it there before doing the maniac flare dance. That's where it tore this time too only all the way up to the base of his tail.
The only other tank I have is a 6 gallon in storage and I'd be more worried about ammonia spikes in a new tank. If he's not better in a week then I'll get a smaller critter keeper for him (oh, he'll be so happy!). I'm thinking I need a stand light in that corner. The tank is up against this totally dark corner so when his tank is lit up he can see himself really, really well. I put white paper there but it almost seems like he's conditioned himself to flare there whether he can see himself or not. He might be looking at getting moved permanently if he keeps up with this.