The Dennerle CO2 Long-Term Test Correct continuously and accurately monitors the CO2 levels in the aquarium. The six-color comparison scale allows you to directly read the CO2 amount in the aquarium in milligrams per liter. This makes it easy and safe to adjust the correct CO2 addition amount.

Meaning of the color reactions: Yellow = too much CO2, yellow-green = a lot of CO2, green = optimal CO2, green-blue = little CO2, blue = too little CO2.

The complete set includes: test container, CO2 Special Indicator, six-color comparison scale. It is particularly simple and accurate thanks to the CO2 Special Indicator: conventional CO2 long-term tests are filled with a mixture of aquarium water and indicator. The disadvantage is that the acids present in any aquarium water (e.g., humic acids, nitrates, etc.) can distort the test results. Additionally, other CO2 tests require prior measurement of the carbonate hardness, as they primarily measure the pH level. In contrast, the Dennerle CO2 Long-Term Test Correct uses a ready-to-use CO2 Special Indicator that is used pure and not mixed with aquarium water. It lasts for 5 months!.