Excellent sand stirrer and scavenger. These snails will pop out of the sand when they smell food, or when you are feeding the fish. Contrary to popular belief these snails do NOT eat algae; they eat detritus and leftover fish food. [...] Your feeding regimen and fish load should be the reference point of how many Nassarius snails you add to your tank.
I've yet to see a Nassarius snail make a pile of detritus disappear... They're good, but not that good...