I feed mine zichinni, some feed cucumber. Either one, make sure their small so the seeds are small and theres more veggie for them to eat. Also it has to be weighted down some how. If you slice it you can put it on a rock with a rubberband. If you cut it long ways you can stick a fork or spoon handle up through it. OR buy one of the special clips for veggies
I have a cucumber and I'm going to make a circle piece and stick a spoon through it to weigh it down and get a veggie clip later but should I wrap the cucumber in plastic wrap or how should I perserve it after I cut a slice off?