Hi JJ, here's a recipe and instructions from Wiki: https://www.wikihow.com/Clean-Bathroom-Grout
If light color, spray with Tilex, let it sit for at least an hour, add to.it to keep it wet. Scrub with a scrub brush using soft scrub. Rinse . Once cleaned be sure to seal so you don't have to work so hard next time.
This is the best homemade grout cleaner I have tried: https://www.craftylittlegnome.com/the-best-homemade-grout-cleaner/
If its stubborn stains, Lysol Lime & Rust Remover Toilet Bowl cleaner, comes in a black squirt bottle. Scrub with Scrub Daddy or Mr. Clean Magic Eraser.
I have Mr. Clean Magic erasers, winching love to use to clean windows. No streaks. I’ll give it a try.
Hi JJ - This is the shower cleaner that we use to help keep grout and tiles clean and minimize the mildew - it works on kitchen grout too. Hope this helps! Hugs, Holly
PS - We have a FREE eBook with recipes for all of my homemade and all-natural cleaners. You can download it here --> https://pinkfortitude.com/thank#GreenClean