Here is a pic of my new rat rack.
Pic of built-in food holder.
Pic of 1.3 rats in tub.
This is my second rack I have built, made some minor changes from the first. It seems to work very well, rats seem fat and happy. With this setup keeping them is very easy. Built-in food holder holds up to a weeks worth of food, right now I am using water bottles but plan on making an automatic waterer. Any comments are welcomed.