A swimming pond is not easy to build. Without the right planning, the project can quickly fail and, in the worst case, even result in high fines.
Swimming ponds combine the beauty and ambience of a pond or biotope with the advantages of a swimming pool. The natural alternative to swimming pools cleans itself and does not rely on chlorine and other chemical agents.
At the same time, of course, you have to consider a few things when creating the pond, which are essential for a long-term intact pond. Paying attention to a few important things before construction saves a lot of time and unnecessary work.
Do you need a permit?
Many people are not aware that ponds often require a permit. However, because unregistered ponds can lead to warnings and fines, you should definitely have your pond approved in advance. This is necessary in most federal states from a water depth of 1.5 meters and a total volume of 100 cubic meters. This is where the state matters. The experts from MCM Systems have created a table showing the legal basis in the individual federal states and what there is to consider in addition by law during construction.
In many areas, for example in neighboring Austria, even small ponds have to be registered. If you build a pond in a local area, it must be registered immediately. Especially with swimming ponds you should play it safe and get detailed information in advance.
Construction of the pond
The pond should be constructed over several levels so that it is ecologically balanced at different temperatures and weather conditions. This is especially important in warmer temperatures when the lower stages protect the pond from algal blooms, lack of oxygen, and increases in nitrogen and phosphorus. So it makes sense to dig a pond depth of 2 meters or more, especially in warmer areas, such as southern Germany.
In the case of larger ponds, it can easily happen that the designed The pond liner has cracks or holes in the bottom caused by sharp stones. To avoid this, it is best to dig the pond 10 centimeters deeper than originally planned and then fill in a layer of small pebbles about 10 centimeters high. This protects the pond liner and also looks more natural. Such work can be very time-consuming and exhausting. If you want to save yourself the work, you can also outsource it. You can find qualified craftsmen with pond construction experience on portals such as Renovero without a long search. In the meantime, you can then deal with other things, such as the pond technology.
Technology in the garden pond: Is a water filter necessary?
In principle, garden ponds do not require any technology as long as the nutrient concentration remains moderate. The larger the pond, the easier it is for the body of water to remain in balance. If you have a small pond, it can help to install a filter system that is activated if necessary. Especially in hot temperatures, this can reduce the algae. It also filters toxins, suspended matter and excess fish food out of the water.
Fish in the swimming pond
Fish and water dwellers are often a particular challenge because they can easily cause a balanced body of water to tip over with droppings and leftover food. Especially when the water has a tendency to rapid algae growth and lack of oxygen due to warm temperatures.
Less is more should be the motto when buying fish to be able to guarantee the he alth of the pond. Especially since young fish often multiply their size in the coming years, you should calculate generously. The experts at Gartenteich-Ratgeber recommend planning around 600 liters of water for a fish with a full-grown length of 25 centimeters to be on the safe side.
Basically: Fish are not part of the ecological cycle of a pond, which is necessary for a long-term balance. Rather, fish are a risk factor that can easily become fatal. This is especially the case with smaller ponds.
Summary:
The more fish in the pond, the more technology is needed to keep the water in balance. You should also pay attention to the diet of the pond inhabitants. Koi or goldfish, for example, like to eat the underwater plants, which as a result cannot displace emerging algae. Other species, such as carp or certain koi breeds, eat also the algae and produce such an opaque green in the water that it is difficult to observe fish from the outside.
Danger of over-fertilization
Probably the greatest danger in ponds is over-fertilization. It increases significantly when holding fish. Fish, algae growth and fish food make the water too rich in nutrients and threaten to tip over. If you keep a lot of fish in a pond of limited size, this is particularly dangerous. Then about 10-20 percent of the water should be changed every week so as not to keep too many nutrients in the water.
Correct position of the pond
Where would you like to dig your garden pond? The body of water is often the showpiece of the garden and is therefore often excavated in particularly bright places. However, it is important not to let too little or too much sun shine on the pond. Five hours of sunshine are optimal for plant growth, but it should not be much more. Sun protection for the pond can therefore make sense under certain circumstances.
Important: Shallow roots with hard roots should not be allowed to thrive near the pond, as they can pose a risk to the pond liner.
Pond care: The perfect pond rarely runs on autopilot
Having a pond means taking responsibility and taking care of it. Especially when fish are involved. This includes, for example, regularly checking water values: What is the pH value of the water? How much phosphorus and nitrogen trioxide can be found in water? What is the total hardness? In his guide, the garden pond professional Tetra explains which individual water parameters are important and how they should turn out.
Even if there is no technology at all, there is always work to be done - for example, a proliferating aquatic plant can quickly fill up large parts of the pond. In this case, you must intervene quickly and remove them.
Even in winter you are often confronted with challenges. You must ensure that the swimming pond remains ice-free so that there is enough oxygen for the pond inhabitants. Ice preventers are suitable for this, for example:
An air pump or an oxidizer for the oxygen supply can also have a positive effect.
Conclusion
A swimming pond in your own garden can be a lot of fun and is basically low-maintenance. The interplay of water and the right plants around it is particularly beautiful to look at. However, the effort involved should not be underestimated. Especially at extreme temperatures, the pond must be kept under control. If you also keep fish in the swimming pond, the ecosystem of the pond is much more sensitive, the use of technology such as air pumps and water filters is then particularly recommended. All in all, building a swimming pond is not rocket science, but it does take time and work so that you can enjoy your swimming pond.