Color Match
Opt for a grout color that is close to the color of the tile you have picked for the pool. Using a contrasting color will cause you to see only the grout and not appreciate the tile you have chosen. If you choose a cool color for the tiles, look for shades of gray grout. If you select warm color tiles, use cream or light brown grout. For example, if you choose a baby blue tile, look for a light gray grout.
Chemicals
Many people believe bleach used to clean the sides of the pool will damage darker grout, but that is not the case. As long as the bleach is mixed with 3 parts water, the solution will cleanse the surface without damaging the grout. Regular pool cleaner also is made to prevent damage to pool grout and will not affect dark grout.
Accessories
Grout is an accent piece to the tiles and overall pool décor, just as any other accessory. The grout complements the tile and is designed to match the overall look, including the poolside chairs and ornamental elements.