Feed the cats by placing food bowls on either side of the closed sanctuary door. How far from the door itself will be determined based on how reactive the cats appear. In subsequent sessions you’ll gradually move the bowls closer.
If one cat eats faster than the other use a dish with some obstacles in it (such as a slow-feeder bowl used for dogs who eat too quickly). If you’re feeding wet food you can also push the food against the bottom and sides of the bowl so the cat has to work a bit harder to get it.
Cat Scent Swapping
Scent is a very important communication tool between cats. With your cats separated, it’ll be important to make sure their scents stay distributed around the house. You want the scents to stay fresh so doing a room swap will help there. The cat who had the run of the house has been freely distributing her scent around but we have to make sure the cat who is in the sanctuary can have that opportunity as well. Periodically do a scent swap by letting the cat in the sanctuary room out into the house to distribute his scent. Before doing this, place the other cat in a separate room temporarily. Then, you can move that cat into the sanctuary so she can distribute her scent there. Basically, what you’re doing is a room swap.
During the scent swap, keep a casual eye on each cat (don’t hover or else you risk making them nervous) so you can distract a cat with an interactive toy should tension start to rise. You don’t want the scent swap experience to create anxiety; the point of the exercise is to remind each cat that the other kitty is still around. Facial pheromones are considered the friendly ones because cats typically cheek-rub on objects in an environment where they feel comfortable or familiar.
You may not have to do the scent swap phase for very long at all. It will depend on how reactive your cats are and how serious the aggression between them has been in the past.