How do i get my dogs to stop eating the cat food?

I have 2 dogs and a cat, and their food is always out but my cats food was always on a little table so my dogs couldnt get to it. But recently I noticed my cat can barely jump on to the table (hes very old) so I started putting his food on the ground. But now I cant get the dogs to stop eating his food, and I dont want to keep using the table because Im not always around to pick my cat up and put him on it. Any suggestions?