BioAlnus – is a condensed black alder cones extract which contains tannins and humic compounds that slightly acidify the water and give it a characteristic golden color. Its low carbonate hardness lowers the pH of the water, and contributes to maintaining the biological balance of ponds. This mixture clarifies and purifies water, which creates good conditions for the development of beneficial bacteria, while naturally reducing algae and fungi development. It reduces the infection risk for fish, by supporting their well-being and immune systems. The mixture is environmentally neutral and safe for people, plants, fish, and other animals that interact with the aquatic environment.

BioAlnus Mixture:

  1. 100% ecological, and safe for humans, animals and the environment;
  2. Reduces the amount of algae;
  3. Acidifies water naturally;
  4. Improves the health of fish;
  5. Prevents fungal infections and mold from forming on roe;
  6. Amount: 500 ml, 5 L;
  7. Yield: 5 m3, 50 m3


Applications: fish ponds, swimming ponds, freshwater aquariums, and “black water”.


Application method: mix the contents of the bottle with five liters of water in a bucket and evenly pour it over the water surface. Repeat the application every 30 days starting from early spring. High carbonate hardness of the water in the reservoir will limit the effectiveness of this mixture. This product may slightly tint the water with an amber color.


Dosage: 500 ml of the mixture per 5000 liters of water.


Storage: Store in a cool and shaded place at above freezing temperatures. This is a natural product, so sediment may form at the bottom of the bottle. Use completely after opening.
How and when to use this product – calendar with application dates


Black alder cones, due to their content of humic acids and tannins, have been used in aquariums for a long time to disinfect and gently acidify water.

Alder cone extract supports the natural functions of most ornamental fish, including their readiness to reproduce.

Ecological sustainability is the selection criteria for the black alder cones used to produce the BioAlnus extract.

BioAlnus acidifies the water naturally; changes in pH differs for each reservoir depending on the pH buffer, i.e. the carbonate hardness (CH). The greater the hardness, the less the pH change will be.

Alder cones are highly recommended in breeding aquariums, and for fish that prefer the so-called "black waters" of South America.