Thanks for the advice szpiano , my test kit is a Taylor K-2006. I followed the directions they show . I have been using a 1"tablets in the chlorinator feeding after the filter and heater.I didn't know that they were stabalized and would raise the CYA. Are you suggesting using only liquid chlorine?

In the steps suggested I'm to add 69 oz of sequestor follow the directions to step 12 then add 69 more Oz of sequestor. I see no menthon of using the ascorbic acid to put the metal that is staining the pool back in solution? When I first did the ascorbic treatment the stains all disappeared. I assumed the metal was in solution and the sequestor would keep it there.Since it didn't , thought I didn't use enough sequestor.

I guess I was lucky for 18 years never having any problems like this!