Does your bathtub slip resistant bottom look like the one the top of the picture below? If so, it may be embarrassing when you have guests come over, right? You may have tried different ways to clean them out, but none of the products seemed to be very effective. Luckily I found this link below and the cleaning product used (which is also recommended in Kohler’s website). The result turned out to be great.
Click below link for full instruction