I use mine so much it grows algea sometimes cause I don't always rinse it off.
Use a tooth brush or a qtip to clean and be careful not to dunk it in the water if it is not waterproof.

Like said, don't let it dry out. Store in tap water or storage solution both just as good. I always keep the cap half full of tap water when not in the storage solution.

Now I always keep a few new ones because my bro's can screw them up faster than I can order them. If they screw up much more I'm going to start a hydro shop.