As others have said, the Mr. Clean Magic Eraser is great. I had some stains on the steps from the end of the hose resting there when I added water. The Magic Eraser removed the stains. Now I am more careful not to let the hose rest on the step, just in the water.

I thought BB's were lead, but I guess not for the smaller guns. (coated steel?)

Boby

I had read that rubbing ascorbic acid (vitamin C) on the spot will take them off, too.

I always worry about what the mystery cleaner is in a Magic Eraser (several of my kids are developing chemical sensitivity) so I don't use it - any idea what it is?

Thanks for the idea of the Mr. Clean Magic Eraser. Used it today and rust spots are gone. Also the stubborn water line. Steps look like new. I have found a new staple to my pool supplies. It is chemical free, it works on abrasives only.