If you are worried about the color of the grout being changed or faded,
then that's one thing. But where you have installed grout, there needs
to be caulking there instead of grout. TRUST ME, the grout won't hold
up being in a joint like that. Similar places are where backsplash
meets a counter top, never grout, always caulk. 90 degree corners in
showers or backsplash., bottoms of bathtubs where it meets the floor,
all around a bathtub ledge where tile meets the tub. Always use 100%
Acrilyc-laytex siloconized caulking. Epoxy caulking is not bad as
well, but with the Acrilyc, you will get more flex if there is ever
movement. The sealer won't be as much of a garuntee in repelling water
over time as caulking would be in that area. Cleaning grout lines can
be a pain if not impossible sometimes and need to be redone. There is
a product out there that is a grout colorant and sealer at the same
time. Works good, I've used it on my jobs. Home Depot only has a few
select colors, but they can order others. There are also grout
cleaning products at Lowes, I like the Aqua Mix brand myself. Hope
that helps!!

Erik
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