Jadnashua
Retired Defense Industry Engineer xxx
The sealer only needs to get on the grout...most tile won't absorb any. It won't hurt it, but follow the instructions on the bottle! It will tell you to NOT let it dry on the tile. If you do, it will leave streaks that will be very hard to get off. They can usually be removed by rewetting with sealer, the stuff will disolve itself, then buff.