The empty shell should be left in the tank, where it will be consumed over the next few days to recover the lost minerals and help form the new shell. Some live longer. Water conditions Not critical. Freshwater, but can tolerate a wide range of conditions. Cool, hard, alkaline, well aerated water is best for most species.
Some species are tropical, some require cold water.
Medium hard or hard water with a slightly alkaline pH, 7.5 - 8.5, is best. They do not need to leave the water. The tank should be covered to prevent them from climbing out and going exploring around the house. They can climb up between the tank wall and a under-gravel lift tube, or climb up plants or a heater. Don't feed too much fat.