Never heard this about hikari gold before. Is it meant to be one of the ingredients?
im not sure what people say it is but if it does make fish aggressive then i guess it must be an ingredient......
like i said ive fed all my fish using hikari products from small tetra to huge cichlids and never had a fish turn nasty from eating it. there are numerous reasons that fish can become aggresive, the main one being a territorial issue as the develop and grow into adult fish that need their own area.
hikari gold is very openly available and must be fed to 90% of cichlids sold so what do they all have in common? they mainly all eat the same food so it must be that.......
how about people that keep large fish in smaller tanks and expect them to just get on? people who dont break the line of sight in a tank by using wood, plants or rocks etc? how about the people that mix a known aggressive fish with less aggressive fish?
many people do things they shouldnt but i bet most feed hikari gold which is too easy to blame in my eyes.