Our cya is over 150, and after fighting with the chlorine for over a month we realized it would be cheaper just to do a partial drain of the pool. There are brown stains all over the pool, which is fiberglass. After doing some research I tried vitamin C tablets on it and of course we were impressed with how it inmediately bleaches out the metal stain. Would you all recommend doing an acid wash while it's partially drained or adding acid to the water after it has been refilled? My concern about the acid wash is that we are not draining all of the water...just about 75%.
I would also welcome any tips on how to balance the water once its been refilled with city water. I've already looked it up online and skimmed over some instructions but if anyone has advice I'm open to that. Thank you!