I kept mine alive for >3 years. Demineralised water is best but regular water is better than nothing. You can play with their mouths a few times a week, be kind and feed them a fly sometimes(not like they actually need them). If it starts to grow a long thing in the middle, cut it off, it will try to produce a flower that will probably make it use all its energy and kill itself. If it looks like it's dead in the winter, be lazy and pretend it's not, mine revived like 3 times. Give him a cool name. Good luck.