As soon as i put food in my tank, my Nassarius snails seem to instantly come out from the sand. One of my tangs ripped out my featehr duster somehow and it fell to the sand, and my Nassarius snails ate it in less than 30 minutes. One of my pepermint shrimp also died mysteriously one day and i found him one of my pumps tubes. so i unplugged it so i could take out his dead body but as soon as it hit the bottom of the tank, my Nassarius snails were all over it and ate every last bit of it. I would HGIHLY recommend them for picking up unwanted food!