I have two cages, one is a FN and the other is a super pet ferret cage. The two girls will stay in the FN and the male will be in the super pet cage. My question is: They pee in one section of the cage and it is staining pretty bad. I try to clean out the soiled bedding and put new in everyday, but it still is a problem. I am afraid it's gonna eventually eat through the plastic. Should I just get a metal liner to put in the bottom of my super pet cage or is there anything else you recommend? Or maybe try putting a seperate litter box with bedding? Maybe they will pee in it?