Your bathroom shower is a damp environment, so you need to do regular maintenance to keep gunk at bay.Soap scum builds up in the tub and on glass doors. Mold and mildew proliferate on grout and tile. And even decorative shower curtains are plagued by hard-water deposits and cloudy residue.Thankfully, compared with other bathroom tasks, cleaning a shower curtain can take a lot less work — especially if you have a washing machine.