The edding chalk markers are easy to remove with water. A surface or wall that has been painted with board paint is often slightly uneven and may not be a completely closed surface. This can often mean that although the colour pigments of the chalk ink can be removed, the written text can still be seen. We call this effect ghost writing. It is not the pigments that are left behind, but the release agents contained in the ink. These are like a colourless film. To remove this, we recommend the edding BMA 1 board cleaner or a soap solution.