Mystery snails make great additions to your tank. They are great at cleaning. They will eat anything but usually leave live plants alone as long as they have other food. I feed mine blanched dandelion greens, spinach, algae wafers, lettuce, and other mixed greens. You can feed Tums or similar antacid tablets for calcium. They love the fruit flavored ones. you can also add egg shells or human calcium supplements. The ones with vitamin D are fine. They can lay eggs without a male. The eggs will not be fertile though without a male. However, if it is a she, she could have breed in the store and hold onto the sperm for several months. The higher the tank temperature the shorter their live. They live for an average of two years.