Hi all,
We have had some discoloration of the grout in our shower. We recently bought the house, so we don't know how the shower was installed, unfortunately. The grout is only getting darker in certain places (it seems like where the water would hit us when we shower and then bounce off and hit the wall). Although, there's water that hits other places that aren't discolored.

Pictures can be viewed here: http://www.flickr.com/photos/90974048@N02/
Pic 1: Full view of shower (toward the right side of the photo, you'll notice the darker grout between tiles).
Pic 2: The darker grout
Pic 3: Regular grout

It does seem to lighten after the shower isn't used, as soon as 60 minutes after. I'm afraid water might be getting in there, and if so, why only here? We tried resealing the grout, but that didn't do much.

Any suggestions? Thanks!

What did you seal it with?
It may take two coats to seal it.

First of all please let us know how old your shower is. This is mainly because of water absorption. Do you have exhaust fan installed, if your bathroom is on darker side? Try to clean it by either removing and replacing or by scatching its surface.

So that's what I've been doing wrong all these years. I'll throw out the grout cleaner and just rip the whole wall out next time and replace with all new tile.
What was I thinking?