Legend CO2 Indicator Solution

Legend CO2 indicator solution can be filled into any standard CO₂ permanent test and serves for the long-term monitoring of the CO₂ level in aquariums. An optimal CO2 supply is essential for the thriving of aquatic plants and should therefore be continuously monitored. The advantage of the Legend CO2 indicator solution is that the determination of the CO2 supply takes place independently of the aquarium water, thus substances such as humic acids cannot affect the CO₂ check.

Size: 120mL

bromothymol blue

The permanent test is filled with 1 – 2 ml of the Legend CO2 indicator solution and then positioned in a well-circulated area in the aquarium. After about 1 – 2 hours, the CO₂ content of the aquarium water can be read. A green colour indicates an optimal CO₂ supply of approximately  30 mg/l.

A Legend CO2 indicator solution is very useful in an aquarium. Often, aquatic plants lack the essential CO₂, preventing optimal growth. With a CO₂ permanent test, the CO₂ level can be controlled with sufficient accuracy. The dye bromothymol blue used has the property of changing colour in a defined pH range.

CO₂ diffuses from the aquarium water through the air bubble in the permanent test into the test solution and vice versa. Depending on its CO₂ content, the pH value of the test liquid and thus its colour changes. A defined carbonate hardness in the test liquid determines at which CO₂ concentration a certain pH value is established. The Legend CO2 indicator solution turns light green when the pH value is around 6,6. This is achieved at a CO₂ concentration of 30 mg/l. For this reason, the Legend CO2 indicator solution indicates a light green tone at a CO₂ value of the aquarium water of  30 mg/l. If the CO₂ supply in the aquarium is less than  30 mg per litre, the test reagent remains blue; if the CO₂ supply exceeds the mark of 30 mg per litre, the test reagent turns yellow.

pH Checker Solution SDS 20210729.pdf

Storage: at room temperature. Protect from frost and heat. Keep out of reach of children and pets.

Use: For fertilization of ornamental plants in an aquarium only.
See the pack for detailed dosage recommendations. Note: Official guidance recommendations take precedence.

CO2 indicator solution 120mL.png