Came back from a trip to see that the Tupperware dish we'd wired to the inside of our pen had fallen apart. Wondering if there is a better way. I found this on Amazon - does anyone use these? https://www.amazon.com/dp/B016L1VWGC/?tag=backy-20 Our pen is basically chain link but 2 ft. of hardware cloth reinforcing it so I think we would have to use wire to secure the hooks. Maybe just stick with Tupperware? I could just put a dish in the pen but they would probably tip it. Maybe that's okay, tho? They would still find the grit.