By "that" thread, are you referring to "http://www.poolforum.com/pf2/showthread.php?7923-Stain-removal-via-ascorbic-acid-treatment"? If so, I didn't see I way I could post the question because it was closed. Sorry for being slow with the threads, but guess I need a little more direction on which thread you want me to post the question on. Be glad to do it once I know where to go. Thanks