Dirt, mold and grime can collect in small spaces like the grout lines between floor and bathroom tiles. The Home Depot's Joe Autry say you have several inexpensive options.
There is a grout cleaning tool that you can buy for a few dollars at a Home Depot. The head of it is a triangle shaped device. You just run it up and down your grout line, scraping off the old, discolored grout. It doesn't take very long, just a little time and you look good as new. Much cheaper and better than the cleaning solutions.
If your problem is mildew, here's what you can do. There are a number of commercial products which you use by spraying down the shower after use. Reading the list of ingredients I noted that the number one ingredient in this "after shower" cleaner is alcohol. Now alcohol will kill mildew, and it is a lot cheaper than buying some name-brand commercial product.
One more expensive option is the Black and Decker ScumBuster. It has a rechargeable battery and several attachments. It retails for about $40. It also cleans into groves and crevices with very little effort.
Baking soda! Just dampen the area (just wipe it with a damp cloth--nothing too tricky) and sprinkle baking soda over the grout. Let it set a few minutes and then use an old toothbrush to scrub it. It really takes minimal elbow grease.
Fill an empty spray bottle with bleach and water (1 part bleach and 1 part water). Just before retiring in the evening, after everyone is through using the room, quickly spray the grout with this mixture. The mold will disappear within 1 - 2 weeks. To keep the mold from returning, spray the grout with this solution 1 - 2 times per week.
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