Hi! My three girls are my first ratties ever so I'm learning as I go! I had a question about fleece liners for the Critter Nation cages. I ordered a set, but then when applying to a breeder I was told they are not good. The girls do have a litter box and we are working on training right now. I was also doing some research on a pee rock. I know the concern is cleanliness and the ammonia build up in the fleece. The set I purchased does have a liner to prevent this and I also wash the babies bedding once a week. Is this sufficient? I'm worried now. Also, I deep clean their cage every Tuesday and rearrange their set up for some mental stimulation. Is that frequent enough? I'm not sure if I should be doing it twice a week... Thanks in advance!