Salifert Copper Profi-Test Copper is often used as a treatment for parasite infested fish and it is essential that the correct concentration is used as too high levels can be toxic to marine fish and invertebrates. Tap water can also be naturally high in copper and it is therefore advisable to test for this on a regular basis. The Salifert test kit offers a very sensitive and accurate test for measuring dissolved or weakly chelated copper with a pH of 7.59. Lasts for several copper cures or provides sufficient for up to 50 tests on tap or aquarium water as a routine check. Can be used for marine, fresh and garden pond water. Strongly chelated copper will only be partly or not at all detected. Warning! KEEP OUT OF REACH OF CHILDREN. Not for consumption. Instructions: Add 2ml of water in the test vial. Add 5 drops of the Cu reagent and swirl gently for 5 seconds. Allow it to stand for 10 minutes. Some copper medications might use strongly bound copper and would require a waiting time of 20 minutes. In case of doubt compare the value after 10 and 20 minutes of waiting. The highest value should be noted. To obtain the copper concentration hold the test vial in front of you. Place the white part of the color chart firmly against the side of the test vial and look from the opposite side. A blue tinge lighter than the 0.1ppm value corresponds to approximately 0.05ppm. A color in between two color bars indicates a copper value in between those two values.