Drop Checker is CO2 density measuring unit, utilizing character of changing pH value according to CO2 amount in the water, and used for knowing CO2 supply reference. When the amount of CO2 in water changes, liquid (pH reagent plus aquarium water) in Drop Checker changes its color accordingly. Usually, the liquid shows blue color before supplying CO2 or shortage of CO2, and shows green color when CO2 is proper amount in water. Also, the liquid shows yellow color when CO2 is in abundance.
Although the liquid in Drop Checker does not make contact with aquarium water directly, as CO2 level changes in aquarium, CO2 level of air inside the Drop Checker changes accordingly and it turns the reagent color. From this reason, water condition of the aquarium water and reagent must be same condition in order to have correct result. So we advise to change the liquid inside the Drop Checker, right after the water change, when the water condition changes significantly. For maintenance, please use Superge, for cleaning the algae. After soaking, please rinse out completely in order to get collect measured result. Please rinse inside the Drop Checker by syringe, as well.
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