Brushing pool the other day and I found small spots (about an inch) that are rust colored. We have an autofill from our well that has red iron. Any advice on treatment for the spots as well as a continual way to prevent them from returning?
Crushed up vitamin C tablets in a sock or nylon can be used for spot cleaning to remove iron stains. However, you need to stop using the well water for fill OR you have to setup some kind of filtration on that line to remove the iron. It's only going to get worse if you keep filling your pool with iron-ladened water.
I had about a dozen of these from dime size to nickel. I just dropped one vitamin C tablet in the pool and used the pole without any attachment to push over the stain. 15 minutes later all gone. The exception was the ones on the side where I took a stocking and placed 5 in there with a small weight and string and dropped it in the pool and the string held it in place. Those took about an hour but again the stains are gone. I have pebble finish as well.