I recently noticed one of my rats eating poop and tried my hardest to stop her. After failing to do so and being disgusted, I went to the internet and found that coprophagy (eating your own poop) is essential to rats. Someone even said that not allowing them to eat their own feces can cause them health problems and ultimately die because it provides nutrients along with beneficial bacteria. Whatever the case is, I am litter training them in a litter pan that has a lid which makes their poop slide through the bars into the litter. The product is called All Living Things Deluxe Scatterless Litter Pan for Rabbits & Ferrets and I used it because some rat owners on youtube recommended it to me. So the question is, what is the best litter pan for rats (corner one preferred) and is it recommended not to have a lid?