After running a lot of tests. I think the Hanna's instructions are wrong for a real world application. Try running a test using 5 ML of Reagent A and my tests now match my tridents, salifert, calibration solutions and red sea.
Do me a favor and redo a test with 5 ML of Reagent A and post your results here. When Reagent A draws air, you get less of Reagent A in the test pushing the numbers high. Try running a test using the tip but using 5 ml of Reagent A. This will allow for error when drawing up Reagent A. Please let me know how this works for you. I think they created the instructions of 4 ml of A based on lab grade equipment, not regular guys doing the test at home, with plastic tips that suck in air and with all the errors we create. Try 5 ml of Reagent A and let me know how it goes for you.
Do me a favor and redo a test with 5 ML of Reagent A and post your results here. When Reagent A draws air, you get less of Reagent A in the test pushing the numbers high. Try running a test using the tip but using 5 ml of Reagent A. This will allow for error when drawing up Reagent A. Please let me know how this works for you. I think they created the instructions of 4 ml of A based on lab grade equipment, not regular guys doing the test at home, with plastic tips that suck in air and with all the errors we create. Try 5 ml of Reagent A and let me know how it goes for you.