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Epoxy grouts are designed to withstand chemical exposure and repel staining. This makes the grout haze caused by epoxy grout the hardest to remove. Before you try to clean the epoxy grout haze, make sure the grout has been set, or cured. This will ensure the grout is not damaged when you clean off the grout haze. Speak to the professional floor installer to find out how long the grout will take to set. You can also contact the manufacturer of the grout for this information. Most epoxy grout takes 4 to 14 days to cure. Epoxy grout haze can be difficult to remove with mild cleaners or scrubbing tools. Try using a professional grout cleaner designed for epoxy grout haze. Use a mop or spray bottle to apply the cleaner to the flooring, then scrub each tile with a white tile sponge.  Avoid using a green tile sponge, as it may transfer color to the grout. Look for a professional grout cleaner and white tile sponge at a tile store, local hardware store, or online. Get an eco-friendly cleaner that is easy to apply. Eco-friendly cleaners usually do not contain toxic ingredients that can be bad for your health and for the tiles. If you are not sure which grout cleaner will be best for epoxy grout haze, contact the manufacturer of the grout for guidance. Some epoxy grout will require a specific type of cleaner to remove grout haze effectively. You can also consult a professional floor cleaner if you need more information.

Summary:
Clean the grout haze once the grout has set. Use a strong professional grout cleaner. Talk to the manufacturer for cleaning instructions.