It doesn't look like fungus to me, is it fuzzy or does it look smooth? The picture you took makes it look like a growth or tumor, in which case it wouldn't respond to a fungus medicine. Lots of water changes will only help since clean water does wonders for fish health, if you don't stress him out in the process (temperature shock, etc).
10g divided; Claude VT & Marie VT | 5g; Gabriel DeT(?) | Mom's 2.5g; Hank DeT