It took 15 days to get free chlorine from 4.5 ppm to zero. So finally this morning I lowered the pH to 7.2 and added 3 lb of Ascorbic Acid. The results are pretty amazing. In 1 hour the liner went from a dingy yellowish blue to a bright clear blue. Even the wheels on polaris and the PVC fitting around the skimmer were stained a dirty yellow and now look bright white and brand new.
I bought a HACH iron test kit and so far have not been able to detect any iron in the water before or after adding the AA. I boiled 250 grams of water down to 10 grams after adding the AA and still no iron showed up in the test. The test is supposed to detect iron down to 1 ppm. I can only assume the test is faulty or the iron is in the form of ferrous and the test will only detect ferric. Has anybody used the HACH kit for iron?
I've decided to take a chance and drain and refill the pool. It has been drained three times for liner replacements and there were no problems with the walls moving or caving in so I'm hoping I can get away with it again. If not the liner is about 8 or 9 years old and could stand replacing. So it would not hurt my feelings it I do have to do some repair.