A swimming pond with fish is technically not a significant problem, but not recommended for hygienic reasons. The pollution of the animals causes the biological balance of the natural pool to be upset, so that bathing fun quickly decreases due to the increasing nutrient content.
A swimming pond should not be home to any fish
What works excellently in normal bathing lakes does not necessarily have to work in a swimming pond. An untroubled coexistence of bathers and fish causes several problems in the long run. As cute as the animals may be, they contribute significantly to the contamination of the pond water, so that fish stocking in the natural pool is more than questionable for hygienic reasons. In addition, people who bathe in the pond water cause considerable stress to the fish, as they use the pond basin with the aquatic plants as a natural cover and therefore consider it their own retreat.
fish and their excrement
A swimming pond with fish will cause increased algae formation in the natural pool within a very short time as a result of their excretions. With the flapping of their fins, the animals also whirl up the sedimented sludge that collects on the pond floor, which leads to accelerated mineralization. Organic substances become inorganic, which ultimately can no longer be broken down naturally. In addition, most fish species feed on amphipods, which were originally intended to act as biological water filters in the swimming pond.
Note legal differences!
While it probably has no effect on the specifications of the country-specific building legislation, whether the natural pool is a fish pond or a swimming pond, it must be noted that there are different strict water guide values for both types of ponds that must be observed. For this reason, the legislature already rules out the possibility that a pool with fish stock is also a swimming pond.
Exceptional rudd vs. cercaria
Harmful microorganisms cause cercariae, which are very unpleasant for our human skin. Anyone who has been running a swimming pond for a long time knows these flukes, which spread quickly, especially at higher water temperatures, and are sometimes brought in by ducks at the pool. In such cases, a single tench or rudd can be used as a natural antagonist, which feeds on cercaria, among other things. More than one fish is not recommended, as the animals reproduce too quickly in such favorable conditions.
tips
Sunfish, moderlieschen and golden tench increase the liveliness of a pond significantly and there is definitely still a little space on the property for a smaller fish pond. As a precaution, we have already summarized the best way to do this in a guide article for you.