What's wrong with my lizards' stool?

I have 2 Western Fence Lizards, and I believe one of them is sick. I really think it's my female, as she's had health problems with her previous owner before (My male, Henry, is wildcaught and notably hardy). To put it simply, her urates and most of her poo is losing shape and form. When I looked in the tank the smell was just awful. She's forming her second clutch. My ReptiSun UVB has about 1 month left on it (it was installed in January). The tank is well-ventilated and they are well-fed. I give her Miner-All every second feeding. She has fresh water. Although he is hardy like I said, I plan on isolating my male if it is serious.