dhoglund said:No I have not tested the tap water but good idea. As far as adding five drops of red.to two ounces of water, I cant tell you why it isn't changing color but it is not (to be fair it might change it a little but no where near anything on the color block and closer to clear than any other color)
Two ounces of water? If you are using the regular color block, there is nowhere near two ounces of sample.