Abstract: In addition to its success in evolving to live on land, Coenobita is a unique and interesting pet as it has no complete exoskeletons and uses gastropod shells to protect itself. However, the artificial shell is at the same time an obstacle as the crab has to adapt to the shell, especially in terms of osmoregulation. The aim of this study was to investigate how to improve the survival rate of hermit crabs (Coenobita sp.) in captivity through the ecological approach related to the artificial shell. The ability of the crabs to change the shell and their survival rate were analyzed by comparing natural shell change and human triggered shell change of C. rugosus and C. perlatus. Osmoregulation was analyzed through water consumption (fresh and salt) and the osmoregulator was used to separate the healthy hermit crabs from the weak ones. C. rugosus had a better ability to change its shell and had a higher survival rate than C. perlatus. In terms of water consumption, C. perlatus consumed more water than C. rugosus did, especially when the salt water was available. Selector osmosis successfully separated strong hermit crabs from the weak ones as shown by their survival rate. Indeed, the survival rate was correlated with the separated groups and was not related to species or media.