Sera CO2 Reagent

Water test refill

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The sera CO² reagent is used for permanent CO² control in freshwater aquariums.

With the sera CO² endurance test, you always keep an eye on the CO² value. CO² is one of the most important nutrients for aquatic plants. A deficiency can, therefore, have massive consequences. The sera CO² endurance test was developed for the permanent control of the CO² content in water. The test tube can be easily hidden in the aquarium, the correct CO² value is simply read off. The indicator liquid is sufficient for 90 fillings.

Easy to use:
Shake indicator liquid before use!
1. Pull off the pyramid-shaped cap and fill it with aquarium water to just under the rim (approx. 1.5 ml).
2. Add 3 - 4 drops of CO2 indicator liquid and put the lower part back on.
3. Turn the test device over and fix it vertically in the aquarium with the suction holder. Please be sure to proceed in this order, otherwise, incorrect measurements and possibly damage may result. Important: Make sure that the lower cavity is only partially filled with water.
4. Glue the colour comparison card from the outside to the aquarium pane near the test device so that a direct colour comparison is possible.
5. After a while, the colours fade in the sera CO2 endurance test. In this case, the test device must be filled again with aquarium water and indicator liquid, as described under points 1 - 3. Then clean the test device.
6. If the cap of the test device is difficult or impossible to remove, the silicone grease on the O-ring has dried up. Then carefully lift off the cap with a small screwdriver and rub the O-ring with silicone grease.

Colour, assessment, impact and countermeasures
Blue: Too little CO2 - take care of plants - increase CO2 supply (note the instructions for use of the fertiliser system)
Dark green: Correct CO2 content
Light green: Too much CO2 - fish are breathing heavily on the water surface or shooting abruptly through the water - reduce the CO2 supply, ventilate well and expel CO2
Attention: The sera CO2 endurance test reacts to changes in the CO2 content in the aquarium water in 30 - 60 min. If the water level in the test device changes unusually quickly, the cap will not close or the O-ring has become brittle and must be replaced. Please check and correct. Close the reagent bottle immediately after use. Store at room temperature and away from light

The delivery includes 1 x 15 ml indicator liquid.

Our expert Oliver Knott recommends:

With the sera CO² reagent indicator liquid, you can always keep an eye on your optimal CO² value!

Brands (Manufacturers): Sera

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