Hello! I’ve been using icp-analysis.com these last few months (since February, at least once a month). Looks like they just changed measurements to ppb from ppm. Some of my most recent readings (7/15 ppb) vary significantly from my last reading (6/06 ppm). Let’s just focus on phosphorus for now. On 6/6, Icp tested phosphorus at .08ppm vs my Hanna phosphate 774 of .10ppm. 7/15 icp Phosphorus 262ppb vs my Hanna 774 .15ppm. I understand they are different instruments but I cannot believe this to be true. My Hanna 736 measured in line with my 774 during my 7/15 year. Wouldn’t my tests vary by the same ratio? I tried bringing this up to icp analysis and they pretty much told me to GFY. Never using them again. Would love some advice before I dose my tank with some lacl
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