Yes the scales on the comparator tubes have different numbers/ranges. The hue/colors on the tube appear comparable to me. The 7.2's for both tubes look the same. The 7.6 on the large is slightly redder than the 7.5 on the smaller tube. The R numbers are different, but I just thought that was due to the smaller sample size of the K1000 so the saturation/concentration would be different. If the R0004 is made for higher levels of chlorine, I would like to confirm that. I always thought the smaller kit was to serve as quick chlorine/ph check to save on the chemicals in the larger 2006 kit. Thanks