Is Copper Dangerous for Your Garden Pond?

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Copper is a trace element and as such represents a part of the diet of many animals. Among other things, it is important to create a variety, for the life of important, enzymes. As previously mentioned designation “trace element” suggests, copper is healthy only in small quantities (traces). At higher concentrations of copper in the garden pond, its inhabitants will become endangered.

Healthy copper concentration limit is crossable rapidly due to various external factors, such as copper wiring, or fertilizers. Especially in shallow water of the pond, a concentration of 0,03mg / l may damage some of the sensitive species. For the elimination of copper in water it is recommended to use Oase Phosless filter cylinders. They had don’t filter out only the important nutrient for algae – phosphate, but also copper. Regular replacement of the filter granulate thus contributes significantly to the elimination of algae and also suppresses the occurrence of copper in the pond.

Copper is particularly insidious because it is a further non-decomposable element and it is not biodegradable, instead it settles in the sediment of the pond. In case of decrease of the pH and the water hardness, the copper, which is bound in the sediment, can be suddenly released and can cause sudden death of fish.

Anti-algae products containing copper

Use of products containing copper in the care of a garden pond, is risky due to the mentioned facts. Algaecides (anti-algae) containing copper must exceed the safe concentration of copper in the pond. Otherwise, the effect of algaecides on filamentous algae will not be sufficient.

Copper toxicity to aquatic organisms

  • 0,03mg / l for algae, particularly blue, and bacteria (also filtering bacteria!)
  • 0,08mg / l for aquatic plants
  • 0,10mg / l for fish

The above data clearly show that the critical limit of the copper content in the pool is equal to algae as to filter bacteria. Moreover, even the fish itself after several applications of such products are threatened, since copper is not biodegradable. If then, for any reason, a decrease of the pH and the water hardness occurs, it will inevitably also mean death of fish in the pond.

The danger of copper therefore lies in the fact that even minimal concentrations kill filter bacteria, even greater danger for garden ponds, however, is that since copper is not naturally degradable, its concentration in the pond will grow in the long-term.

Photo: rohitsute