How Soon After Grouting Can I Seal?
If a solvent based sealer is to be used, the grout needs to be completely dry. Usually 7 days in dry weather is sufficient.
A water based sealer is usually ok at the 3 day point of dry weather.
Aldon "Same Day Sealer" can be use the same day as grouted or years later.
Grout is considered "cured" in 30 days. This number comes from concrete hardness recommendations of 28 days to achieve 90% of ultimate strength. This cure time does not relate to sealing.