i change the fleece every week on the dot and vacuum it twice a day. Lately though it seems like it is not enough. it seems as though either my cavys are not pooping right or they are running it over. their poop is breaking into pieces and getting stuck in the fleece and also it seems like every new fleece that i buy to put in to have extra-extra on hand, they seem to urinate on more. after about two days without changing out the fleece and the lining under it, it becomes stinky. im washing them detergent and vinegar and not using dryer sheets like has been described on may sites. They have also been drinking a lot more than usual but still have their regular amount of vegetables and pellets along with an never ending amount of hay. this just starting happening recently, like Friday recently. is it something that im doing wrong or are they sick?