I don't know much about geos other than they're cichlids I believe lol I've kept cichlids that are supposed to be strictly herbivores like buttikoferi and certain specimens would eat little fish. So those 1' ones would worry me. You should also worry about there attitude, afaik geos aren't aggressive like other cichlids but nonetheless a little territorial, if that's not the case with your specimen I'd still worry for the vatf being intimidated and scared and instead of feeding and thriving he could be worried about running from the much larger geos. The red hooks and 6" ones I wouldn't worry bout however.