This video about cleaning grout lines using a few household items has some good ideas but misses the mark in a few areas. I’m sure this is an effective solution for cleaning grout lines, but I would not suggest using straight Hydrogen Peroxide on your tile. It could damage your tile finish and weaken your grout. I would also recommend using a much larger grout brush that is on a pole so you’re not scrubbing on your hands and knees.
There are some good over the counter tile and grout cleaning solutions but I understand the virtue of mixing your own grout line cleaner. Down in Tampa FL we have a lot of tile and grout floors, so here is a great solution for cleaning grout lines on tile floors
Grout Line Cleaner
½ cup ammonia
½ cup vinegar
¼ cup baking soda
1 gallon water
Mix all the above ingredients into a mop bucket and stir until the baking soda dissolves.
Apply the solution to the floor with a floor mop, then scrub the floor with a floor scrubbing brush. Don’t use a small brush like in the video, it will take all day. After letting it sit for about 10 minutes clean it with a clean bucket of water and the mop. Change the bucket water often to make sure you are rinsing the floor with clean water only. Changing the bucket of water after every 4-5 dunks will keep the rinsing water clean. You could also use a swifter or other mop head that has microfiber pads that can be changed out instead of a bucket of water.