splotchy grout? What did I do wrong?

Hi guys,
I've just finished tiling and grouting by bathroom floor. I used porcelain tiles and what I thought to be a very good grout. However, the grout was supposed to come out a rich dark brown. Instead, its a very light brown and dark splotches in it. I wouldn't worry so much except for the uneven colors. I followed the directions on the package to a tee, so I'm just wondering what in the world made it come out this way? Also, any ideas on how to fix it? I'm thinking the sealer should 'darken' it a little...

a million thanks in advance

If you use too much water to clean up, you can wash some of the colorant out of the surface and you can cause some of the laytex (if it was modified) to form a skin coat on the top.

Carefully scratch it a little in an out of the way area to see what's underneath. If it is the right color, then mix up a solution of 1/2 plain white vinegar and water and scrub it a little to see if you can restore it to the right color. This will remove a little from the top surface. Flush with clear water when done. Acid in the vinegar is pretty mild, but still will disolve a micro-fine layer off the surface, exposing what's underneath.

For good tiling advice, check out www.johnbridge.com.