brooklenella takes time to heal so heres more info..
im sorry i wasnt very detailed in treatment
you want to do the treatment once daily for every other day for 3 - 5 treatments total in the mean time you could...
try to keep the best water conditions possible i would probobly do a 10% water change every 4-5 days.
also i mean you dont have to but you could feed them garlic to help boost his imune system.
DO NOT OVERDOSE ON FORMALIN.
good luck and keep me updated
(sorry for the bad spelling lol)