I used to have a metal based stool close to my critter's waterdish. Which, I might add, I didn't think much about. Well, I decided to lose that stool and when I moved it, there they appeared, rust marks that I can't get off my new flooring. Sure, if I kept my floors cleaner more often, they would not be as distinct or as large. I'm bad at floors but in my defense, only my critters eat off them. Well, we do have the 5 second rule and here, we add a race element. Jolly good exercise for all. Can anyone please help?