My husband and I installed tile in our bathrooms when we first moved into our home. As a foreclosure, the home had moldy carpet (ick!) in the bathrooms. Removing the carpet was a priority for me before we moved in our family. However, there was a lot of tile to install and we only had a short time before we needed to move. As such, the grout job was a bit rushed and therefore a bit sloppy. It was a pain to fix the grout. My husband and I used vinegar to fix the problem and it worked!
Check out the video below to see how we fixed the messy grout problem: