My garage floor is 50 years old and with 50 years of spilled oil, tranny fluid, paint, resin and who knows what all else ground into the concrete floor. I also had lots of small holes and some cracks here and there. I filled those with Bondo and sanded down the excess.
As many of the reviews have said, its extremely important to start with a clean floor before you apply the stain process. So, I cleaned this grimy floor for the better part of a week, using three different types of environmentally safe cleaners and degreasers, washing down with water after each cleaning. I used KrudCutter twice, then followed up where needed with Oil Eater Cleaner Degreaser for the oily areas, and Citrus Strip Paint and Varnish Stripping Gel for spilled paint. Then I used Citric Magic Heavy Duty Cleaner Degreaser one last time over the whole garage floor and foundation walls. I did not pressure wash. And after trying a couple of test spots with stain, I decided the etcher/degreaser was not necessary. After that I followed the Manufacturer’s instructions for the stain prep. I used the bonding primer because i had a lot of dark spots remaining. And after applying the stains (letting each color dry before adding the next), I used two coats of the Low Luster Concrete Sealer. The end result turned out great, no issues, and looks fantastic!