I'm not generally a fan of reduced-whatever pet foods (generally lots of high-priced fillers), but in your case it might be a good idea. Since you WANT fillers, LOL. And Innova is a good brand, no matter what formula you use---if I were going to use a low-fat food, Innova looks the best. I guess their filler of choice is pea fiber, and that's not bad. You could also give your dogs some green beans to help fill them up (frozen have less sodium than canned).