"10Squared" wrote in message
...

Don't use the premixed stuff, pick up some grout that you mix with water
and
just follow the directions. I just did the same thing. It worked fine in
the shower. I probably let it dry for about 4 hours before letting it get
wet. Vinegar is useful for getting the powdery stuff off the tile.

Premixed grout worked fine for my patch job. If this always happened with
premixed grout, no one would ever buy it. Something specific is wrong - bad
batch or something?