Rather than use a toothbrush, I'm pretty sure that if you went into Fethiye, you might be able to by a deck scrubber(no gags please.)They're made of the same material as the pads used on floor buffers. That way you get your tiles & your grout spotless. They are aboy 10" x 4" & you just slap them onto a plastic pad with a pole attached, would take no time at all. Hope this helps. I think they're made by Scotch.