So got my new dpd powder in and the verdict is: old powder was bad. New powder showed 20ppm at the end of a VERY hot day here and not adding anything since last night. Ran a test right behind it with old powder and it gave me a reading of 13. So I'd venture to guess I was bringing my FC to around 30-40 (or more) the entire 5 days. I will say that the pool is super sparkly today so I think last night may have been when the algae finally lost the battle. Will do an oclt tonight to verify. All this said, my DPD expired in 2016. Not sure what the shelf life is but definitely don't go 8 yrs!!
