aquarium fish tank ph no2 no3 water quality test kit

['helps to understand the water quality of your aquarium, and keep the water at most suitable condition.', 'do not place the test tube directly into the tank for moisture testing, add water to the test tube with suction pipe.', 'a perfect and necessary item for you aquarium, provides a clean environment for your fish.', 'keep children away from the testing kit to prevent any necessary hurt. ']