In the cage with yellow fleece, my guinea pig's pee would be like a red, then it would turn dark and then disappear. I then saw it again and blotted it with a paper towel, and it was orange pee. I have my guinea pig roaming around now on a white towel, and he peed again and it's definitely an orange pee. In between a regular orange and a pastel orange, its pretty light. I brought my guinea pig to the vet the other day for another health problem and he did a full body X-ray. turns out the little guy was only bloated, and that was the only health problem, so i know it's not kidney stones. He doesn't make any noises when he pees either, so doesn't seem like he's in pain. Any advice?