What varieties of snails have a good appetite for dead plant matter?
If the snails are going to consume dead plant matter then it should be expected they will also thrive on healthy plant matter as well. The only snails I can think of off the top of my head that may be of some help to you are Malaysian trumpet snails. They tend to eat most specifically detritus rather than attacking live plants as most other snails will do. Freshwater nerite snails may also work for you.
