When I bought my contact lenses a couple of years ago I clearly read through the instructions for using them.I remember the information about the special liquid you put your contact lenses in. It said you should only use this particular liquid to rinse the contact lens case with, and to not use tap water, as it is never as sterile as the liquid.
I'm writing this tip because I know of people that do rinse their contact lens case in regular water.Just be aware that this can lead to having a bigger chance of getting an eye infection.