Shotgun pellets or BBs in bottom of pool

Today while cleaning our pool, I noticed 5 or 6 dark reddish brown spots on the bottom of our vinyl liner pool that weren't there a couple of weeks ago. I tried several times to vaccuum them up, but it finally dawned on me that it was some type of stain on the vinyl. When vaccuuming the last spot, I noticed something kind of roll out of the spot. So, I got into the pool and fished the item out. It appears to either be a shotgun pellet or BB, perhaps a small ballbearing but I can't imagine from what.

Does anyone know what may remove the reddish brown stains that the pellets have left on the vinyl liner?

Lots of folks on the forum report Vitamin C tablets (ascorbic acid) as effective against rust stains. Apply the crushed tablets directly onto the stain.

Sometimes ascorbic acid does not remove rust stains. Try a Mr. Clean magic eraser - it should do the trick.