HELP, how do i treat them?

[Cristeu3]

I got them a few days ago, i suppose on one axolotl a piece of its leg is rotting away or has been bitten(put methylene blue on the wound), also some gills are gone on both of them(the remaining gills have no hair).
They were in a 80l aquarium, used denitrol and biotopol. Pretty sure water is clean, since from tap its going trough 2 filters.
Did some research, i tubbed both, temp is around 17C (using ice packs under the tub to keep it sort of constant)
What do they have exactly? How can i treat them? I need some help here

v

 

[wolfen]

test the kh gh of the water, water filtration (the type that's used on drinking water) tends to remove some carbonates and minerals from the water, axolotls are slight brackish moderate/hard water animals, use a solution such as holtfreters to ensure adequate salts/minerals.
tub using glass/pyrex/ceramic to avoid further infection, keep them tubbed until tank is cycled, feed balanced diet, feed at night, change water in morning, give both 10min methyline blue baths (half fish dose) daily 1 week (two for injured axolotl).
Axolotls - Requirements & Water Conditions in Captivity