Could someone please help me out determining the best most accurate way to find out the cya level? I have a Taylor 2005 test kit. The cya markings go from 30-100. The way I have been doing the test seems extremely subjective. I mean the disappearing little black dot? I can't tell if I see it or not, or just the way I'm looking down at the tube, the way the sun is pointing. I get ranges after anywhere from less than 30 to 40. This leaves me with what target FC level to go with. I have tried to be consistent with my back towards the sun and the tube in the shadow but I just never get the same reading. Is there a better testing method or am I just stuck making educated guesses?