I don't keep anywhere near the amount of crix as most of you but for the few dozen I keep at a time I use paper toweling on the floor. This way I can just roll it up and toss it then put down new. Another is large cardboard boxes. after a week or two (or whenever needed) you recycle the box and move them to a new one. My brother owned pythons, geckoes and a bunch of other herps and he did it this way. He placed a window screen on top.