How to replace black moldy caulk and clean a tile shower. Ugh. Gonna have to do this with one of our showers since every other pinterest tip on cleaning moldy caulk just ain't making it looking good as new! Ewwwwww.
There are specialty tools designed for removing old, stained, cracked tile grout, but few work as fast or as well as the multitool. Attach a carbide-grit grout-removal blade, and use it to grind grout from the joints between floor tiles and wall tiles. Since the blade oscillates back and forth and doesn't spin like a grinder, it doesn't spew grout dust throughout the room. Grout-removal blades come in different thicknesses for use on narrow and wide grout joints. - PopularMechanics.com
DEWALT Oscillating Fast Cut Carbide Grout Removal Blade