Hi Fred:

Please do 4 things:

#1 - Retest with the K2006, and report a full set of results.
#2 - Clean your filter again, and see if there's still any "green stuff" on it or running off.
#3 - If there is any green stuff, catch some in a glass container, and add a teaspoon of bleach. Let us know how that affects the color.
#4 - Let us know EXACTLY what each chemical is, that you've used since first posting, and also if you have any 'devices' on the pool that are supposed to help with the chemistry.