Red Sea iodine test question

[billygoat]

So, a confession: I've been blind-dosing small amounts of Brightwell iodine supplement once a week for the past month or so. I finally got a Red Sea iodine test kit and was eager to see the actual numbers, but the results have left me somewhat confused.

 

 

This test calls for a "standard" vial full of RO water (right) and an unmodified vial of tank water (left). Drops of reagent are simultaneously administered to each vial to begin a reaction, and when the color in the "standard" vial matches the background (0.06 ppm), the tank water vial is "done" and a reading can be taken. According to the directions, the "standard" vial takes 5-15 minutes to match color, at which point the reading in the tank water vial is ready. Mine, however, matched color immediately. The photo above was taken literally seconds after adding reagent to both of these vials to begin the test. If this is an accurate representation of my iodine levels then I guess I am actually more or less spot on, but I have my doubts about the accuracy of this test. The "standard" vial is matching color awfully quickly, and in addition the directions state that the reading in the tank water vial will remain accurate for five minutes, which is very much not the case; it continues to change color constantly. After the allotted "5-15 minutes" mentioned in the directions, both vials have lost their color and turned more or less clear.

 

This is all very confusing, and I am uncertain as to whether I should take these results as accurate or chalk them up to bad reagents or faulty methodology. I repeated this test three times tonight and got the same result each time. Does anyone have experience with Red Sea iodine tests? I'd be very curious to hear if this has happened to anyone else.

[DSA65PRO]

You are okay on your test results, the warmer the water the faster the color matches. I always float both the vials, with them touching in the tank water, so the temperature is the same in both vials. You just need to watch the the right vial, for the color match and not get distracted and miss the reading window. Now the Magnesium, that’s the one I always doubt my results. 

[mcarroll]

I think you need to have the sample on the white background in order to compare with the color card, don't you?