I would try similar to snails. Put a bottle with a small opening with some food in it. Pull whenever have a chance and see stars and replace the food when pulled.
Just curious - why do you want to get rid of them? They are one of the best members of your CUC and will self-limit their population depending on available food
Just curious - why do you want to get rid of them? They are one of the best members of your CUC and will self-limit their population depending on available food