Had a Kinetico rep out to the house today, very nice and knowledgable fellow. He got similar results, ~11 ppm total iron untreated and 6 ppm after the softener. Unfortunately he said the remaining iron was colloidal and said he wouldn't even try to sell me one of their units. Given the relatively sudden change in my well and the fact that it fluctuates he suspects the well pipe might have a hole in it. I take it the only way to get at that stuff is with chlorination but I am going to get the well checked first before proceeding. Thanks for the help and suggestions.