Lisa- I wouldn't use deli cups. I havn't tried them but I am taking a guess that even when filled with water, a snake would be able to push it over and make everything wet amd boy...that would take a long time to dry and could quickly raise the humidity level and stress the snake. I personally use those heavy brown catfood bowls witht he blue insides. They are very heavy and impossible to tip. That's just my opinion though...