Hmm maybe add some aquarium salt to help the healing process and watch him to make sure it isn't infected. If you think the tank can tolerate it, I might also slightly raise the temperature in case it is parasite related.
I would just do water changes and keep the nitrates below 20ppm. You could also do a methylene blue bath for 30 minutes. About 1ml per gallon for 30 minutes.
Thanks for the correction and awesome article. I was not aware that it was not beneficial for healing. I assumed the drying of wounds and desication of single-celled organisms due to the change in osmolality would apply in the aquarium. Thanks!
Looking a lot better today!! As for the salt he is in a planted tank, and my spare is being used ATM. Hopefully it looks even better tomorrow!! If not I will prolly go the medication route