Bunnies of Snails?

maybe, but you'll need a breeding population of snails to feed to the assasins first.
 
Not sure, but a goodly number. They reproduce fast and grow faster. What do you mean by "tub a wear"? Tupperware?
 
Well, you theoretically could, although it would be difficult to stop very small newly hatched snails from getting through even tiny airholes, your best bet would be to cover it with cheesecloth or a similar substance.
 
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