JBL PROAQUATEST CO2 pH permanent Endurance test to determine the acid/carbon dioxide content in freshwater aquariums Simple and safe control of the water parameters in aquariums. Permanent direct measurement of the optimal pH value and carbon dioxide content for freshwater aquariums Long-term test for fertilizer control: Put the reagent in the long-term test device and attach it to the pane of the aquarium with suction cups. Compare reagent color with color scale label and read value Display of pH value (6.4 - 7.8) and CO2 content On the JBL homepage in the Aquarium theme world you will find detailed information on water analyzes and problem solving Scope of delivery: 1 CO2-pH permanent test, display container with suction cup, 1 reagent (+ 1x refill) and color field sticker. Refill reage.