sorry to read of the first part,glad to read the second.
this what i say is a little too much,too late i know......
any fish like this with barbels or spines you are best to catch
in a jar ! plastic jugs work well for this operation, and if needs be
perhaps a bucket.i learnt the hard way to in the begining,
and almost killed one of my bristlenosed catfish.
i hope he stays well.
the only other thing perhaps som melafix to keep and secondary infection
setting in.when you finish medicating you can run some
carbon in the filter,and do your regular water changes.