Monitors water parameters in aquariums easily and reliably. It measures pH (three ranges), carbonate hardness, total hardness, ammonium/ammonia, nitrite, nitrate, phosphate, iron, copper, silicate, oxygen, and calculates the CO2 content using a table. Add the reagents to the water samples, compare them with the color scale, read the values, and check the analysis sheet to see what actions are recommended, if any. The comparison system takes into account the natural coloration of the water. The CO2 content is determined based on the pH value and the KH value using the table. It includes a child-safe reagent bottle in a waterproof plastic case. Refill reagents are available separately.