How to Darken the Color of 3M Colorquartz Swimming Pools

Drain all of the water out of the swimming pool. Wait for it to dry out completely, which may take more than one day.

Sand the faces of the Colorquartz tiles using a belt sander with an aluminum-oxide belt, which is more durable than the usual belts. This will remove the glaze on the outside of the ceramic, which would otherwise prevent the new color from sticking.

Scrub the tile surfaces with a scrub brush and oxygen bleach. The new paint will need a clean surface in order to stick properly.

Vacuum up the residue from the sanding and scrubbing with a wet/dry vacuum cleaner. Allow the pool to completely dry again before proceeding.

Apply a layer of primer to the tiles. This will help prepare them for the paint. Allow the primer to dry fully before proceeding.

Apply a layer of ceramic-tile paint for swimming pools in the new darker shade that you desire. Do not try to use a lighter shade, as the original tint can show through a lighter color. Allow the paint to dry and add additional coats as needed. Once fully dried, the paint will be glazed as hard as the original ceramic finish.