Iodine is an oceanic trace element that is responsible for the vibrant colors of corals, mollusks, and other invertebrates. The Salifert Iodine Test measures all naturally occurring forms of iodine such as iodate, iodide, molecular iodine and hypoiodite. Iodine supplements can change within hours into iodide or iodate, so if you're not measuring all forms you could get a false low reading, which is dangerous as adding too much iodine can be stressful to your aquarium.
This test kit has 2 different procedures. The first procedure measures iodide only, and the 2nd procedure measures iodate and molecular iodine. No other test kit measures all forms of iodine, so you simply cannot get a reading this accurate with anything else.
Iodide Procedure:
Rinse test vial before use with a little aquarium water and add 2 ml of water with the syringe.
Add 6 drops of I2-1 reagent and swirl gently for 10 seconds.
Add 6 drops of I2-3 and swirl gently for 2-3 seconds after each drop (I2-2 is omitted in this procedure).
Exactly 4 minutes after adding this reagent compare colors with the iodide part of the color chart by holding the test vial with its side firmly against a white piece of the color chart and by looking through the opposite side. Waiting longer than 4 minutes will cause further darkening of the colors. For color comparison use diffuse daylight. Sometimes the colors can have a more yellow tinge depending on the color temperature of the light.
If the color turns to blue, purple or black or a precipitate forms then the iodide concentration is far above 0.2 ppm.
After each test rinse the test vial about 10 times with tap or RO water.
Combined Iodate and Iodine procedure:
Rinse test vial before use with a little aquarium water and add 1 ml of water with the syringe.
Add 6 drops of I2-2 (I2-1 is omitted in this procedure) reagent and swirl gently for 10 seconds.
Add 6 drops of I2-3 and swirl gently for 10 seconds. Allow to stand for 3 minutes.
Now look from the side of the test vial. If the color is a dark yellow, green or blue or even has several blue colored particles in it then this suggests that the iodate concentration is far higher than 0.2 ppm and a precipitate can form in an almost colorless solution with tiny blue particles.
If the iodate concentration is not far above 0.2 ppm:
add 5 drops of I2-2 and swirl gently for 10 seconds. Now compare colors with the iodate part of the color chart by holding the test vial with its side firmly against a white piece of the color chart and by looking through the opposite side.
After each test rinse the test vial about 10 times with tap or RO water.
