Mike, I will bring our test kit as well. I would like to compare the results to other test kits since we use the NatuReef test kit for Cal, Alk & Mag testing. It always shows Cal at about 480+ . We haven't dosed the tank w/ Cal in over a month and only adding Natu Reef - Reef Former (which is like Kalwrasser (sp) to our RO water at 1/3 the amount of what should be use. So it should be interesting to see if the test kit is working or not.