Lmk

I would imagine “shock” would do the trick. If the levels of citric acid are high and they break down chlorine levels that is an oxidation process. More chlorine will eventually oxidize the large amount of citric acid and shock is a strong mega dose of chlorine. I welcome any correction to my theory, as I’m no pool expert and looking for a solution to my rusty water. I wondered about citric acid because water softener experts told me to add that to help and seems like it’s work similarly in the pool! Good luck to all as I feel like I need it too! Lol