I'm sorry, I misspoke. When I said hard urates I only meant to differentiate between the white stuff and the liquid. They were not unusually hard.
This particular snake is my fiance's, staying with me for the summer. It has reptile carpet, which I will not change as it is his choice. The snake got washed each time because each time he peed in his hide, then remained there on top of it. He was covered in it, and both he and all of his stuff went in because it is simply easier for me to wash it that way.
To Animals as Leaders: The rats are frozen, and perhaps they are labeling smaller rats as large, because I am buying by his diameter. These "large" rats are the same size as he is, and I am under the impression that that is fine, regardless of what the label calls it.