how big are your gibbys now? its crazy how easily fish can regenerate like that. love the p. scrophus also.
make sure you get your oscar a nice variety of foods if you are going to continue with the hikari pellets. try him with frozen peas, night crawlers, krill, etc... if you want to avoid the hassle and still make sure they get all the nutrition they need so as to avoid HITH you can just feed NLS pellets which have pretty much everything they need to stay healthy and colorful.