Fin & Tail Rot Treatment

[SKIPJACK1963]

I have a magenta pseudo chromis that needs to be treated for fin/tail rot (fungus) but has been impossible to catch with a net or a fish trap in my reef tank for the past 5 days. I would prefer to treat in the hospital tank that I set up but he is not cooperating! and I'm trying to avoid tearing the tank apart. Is their a safe way to treat in the reef tank without harming the soft/hard coral and invertebrate residents?

70 gal reef
water chemistry parameters all in line

Thanks