to read that high on the K-2005 you had to use a dilution of the pool water. the first test with reagent 1 and 2 will give you FC, adding reagent 2 will give you TC. if the color doesn't get deeper when you add reagent 2 you have no CC. If it gets deeper red then subtract your first reading from this one to get your CC. There is no way the color will get lighter unless the DPD is bleaching out from high chlorine levels. If this is the case then you need to dilute more!