I have 3 baby flyers, about 8 to 9 weeks old. What type of cage bedding can I use to help eliminate odor. I am presently using pine bedding. I place a piece of flannel in the cage that they use about 50% of the time and I change that daily. I am cleaning the cage every 2 to 3 days but the order, I assume from urine, is back in a day. I really need to solve this if I am going to keep them inside.