Snail Graveyard

[Beverly]

Every couple of mornings, I find another dead snail in a specific spot in a well traveled throughfare under the LR in my 120g. Fish and corals are doing well in this tank and the snails appear to be active and thriving, except for this one spot. Nitrate is 10 ppm and water changes and other maintenance is done weekly.

I think something living in the rock might be killing them I have a 4" well-fed blue sided wrasse in the tank as well as a Brazilian flameback dwarf angel (Centropyge aurantonotus). Neither one has been seen harrassing the snails during the day.

This morning I found a dead bivalve I didn't know I had in that same spot. Any ideas what might be killing my snails?