For heated water swimming pools with glass mosaic tiles, epoxy grout is highly recommended. Epoxy grout, like the CEG-Lite 100% Solids Commercial Epoxy Grout, is ideal because it is: Water-resistant: Prevents water absorption, which is crucial for submerged areas like pools. Chemical-resistant: Withstands pool chemicals, ensuring durability. Stain-resistant: Maintains its appearance over time. Strong and durable: Provides a long-lasting bond for glass tiles.