Have inside cats and dogs, some are on diet food due to weight issues some on hair ball food cause of long hair. We segregate them or segregate to groups the ones that don't over eat, Your going to have to have feeding times. You can feed an animal once or 2x a day and they will not be harmed. Food bags actually say per day or one time feeding. My wife works at a vet as an assistant, so I know a one time a day feeding will do no harm. Our dog eats 1 time a day and this is when we eat dinner. We put her food down and she eats till full, the cats then try and steal it while she watches or chases them off till tired. No fights at all between dog or any cats other than the little hissy spats.
Individual feedings is what your going to have to do, don't leave food down this is how animals get fat.