i got 6 baby snails from my LFS, they all seemed so happy eating the algea on the glass. a few days later i noticed a blue snail shell, it was empty and i took it out, no sign of the snail nearby, i saved the shell and said oh well 5 left, today i have found the shell of my biggest baby snail also missing inside, no snail, only 1 snail left in my tank whats going on? i only have 1 swordtail(female) 1 play (female), occationally the snails are picked at but nothing major, so i thought..... any clues??