Quick and easy

CO2 QuickTest


  • For the fast, simple determination of the CO2-content in aquariums
  • Result in just a few seconds
  • Easy application
  • A color reaction specifies the CO2-content:
    • Yellow = too much CO2
    • Yellow-green = much CO2
    • Green = CO2 ideal 
    • Green-blue =  little CO2  
    • Blue = too little CO2


Carbon is the most important nutrient for aquarium plants. Approximately 40% of the plants dry mass consists of this vital element. Carbon, or more precisely, carbon dioxide (CO2), is usually lacking in an aquarium - the result: poor plant growth. And when the plants grow poorly, the unwanted algae take their chance. 

With this test you can easily determine whether the aquarium contains enough CO2. Simply fill the aquarium water into the test tube, give it a quick shake and seconds later the color reaction will reveal the result. In case the aquarium contains too little CO2, the use of a CO2-fertilization system is recommended. 

The plants will reward it with lush growth, strong leaves and rich colors. And the annoying algae will no longer have much of a chance.

Tip: When using a CO2-system, we recommend the Dennerle CO2 long-term test Correct +pH for permanently monitoring the CO2-content in the aquarium.

Item no.Pieces
  • Application
    • Fill test tube half full with aquarium water.
    • Seal tube with the cap.
    • Shake several times until reagent is dissolved.
    • Compare color of the solution with the color fields.