Especially when a garden pond looks like something needs to be done against the algae, the algae seem to form and multiply out of nowhere. Especially the thread algae, they are not called that without reason, but they form beautiful, long threads that gently sway through the pond and “ensnare” other plants, roots and sometimes even clumsy young fish with their threads. These thread algae seem to appear all at once as if by a miracle and then in a very short time to become longer and longer, as if some magical creature here “spins green threads” under water.
It is of course not like that, the filamentous algae have just entered a stage of development that is more visible to us than the winter existence of a filamentous algae. So the thread algae are always in the pond, and they are just one of the different types of algae that populate your pond, and the algae (and thread algae) deserve to be in the pond too. Because algae are an important part of life in the garden pond, and in a healthy garden pond they live in a balanced coexistence with the other aquatic plants, fish and microorganisms. This balance is the be-all and end-all of the “lifeworld pond”, but like every natural “organism” it is subject to constant change and adaptations to it, and this also includes the fact that some algae can be seen and that the water in the pond is not in every one Depth is see-through.
If you notice a few thread algae or other algae in the garden pond in the spring, this is not necessarily a reason to fight them immediately and using all possible artificial aids.
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How clear does the water in the garden pond have to be?
If the water in the garden pond gets a slight green cast from the algae, there is no reason to panic.
Because especially among the completely new garden pond owners there is an idea that has little to do with the intact reality in the pond: People often dream of a garden pond that is transparent to the ground, with water that is always clear like the waterfall Mountain spring rises. The water in a healthy garden pond will never and must never look like this; on the contrary, completely clear water in the garden pond would only be a desirable living environment for the plants and fish in the pond for a very short time.
Quite a few newcomers with a pond still have impressive careers on the way to clear water in a garden pond. In the course of his first years with Teich, he got to know every manufacturer and supplier who had something to offer in pond technology or pond chemistry, and if he had spent several years learning everything about artificial water management in garden ponds, he would do it sometimes (but very rarely) even to an artificially maintained equilibrium in the pond, which ensures clear water with constant care.
Completely exaggerated: The water in the garden pond doesn’t really have to be clear to the bottom, the legendary ponds of the most famous Japanese koi breeders are anything but crystal clear, quite the opposite. Kois obviously feel more comfortable in a pond in which they can also withdraw from time to time – it is even known that sunburn symptoms have to be treated more often in our Kois in the summer; these are probably the Kois that are kept in a pond looks more like a shop window than a natural space.
All other creatures in the pond see it no differently than the Kois, every pond inhabitant would like to be able to retreat into a “cloudy hiding place” from time to time, and then there is the fact that the clarity of the water does not have much to do with the water quality – clear water is no more automatically good water than cloudy water is bad water.
If you do not feel excessive ambition in the direction of “technical water management”, but rather see a small oasis in your garden pond, which should help you to more relaxation, you should rather rely on the fact that life in the garden pond settles into its own equilibrium and not try to use a lot of technology or chemistry to ensure crystal-clear water in the garden pond.
This includes learning so much about the “life system of the garden pond” that you notice when the biological balance in the pond is obviously disturbed and you have to intervene.
Create the garden pond correctly
You will learn the first steps in this direction with a professional installation of the garden pond.
When setting up the pond, you should ensure that no garden soil and, above all, no fertilizer can get into the pond. You can do this e.g. Make sure, for example, if you raise the pond slightly and surround it with a drainage ditch which you fill with a thick layer of drainage.
A garden pond should not lie in the sun all day and with its entire area, some “pond dwellers” (this also includes plants) can utilize a lot of sunlight better than others, so the biological balance in the garden pond could quickly become unbalanced. A garden pond should therefore be at least one third in the shade.
Likewise, it is not recommended to create a garden pond in such a way that there are plants around it, parts of which are constantly falling into the pond. The garden pond also needs a certain minimum depth and amount of water, in very small and shallow bodies of water you have to reckon with water and algae problems.
The pond soil should only consist of nutrient-poor sand, and you must not add too much of this to the pond. The pond water added at the beginning should be tested tap water, without phosphate enrichment, or low-phosphate groundwater.
The garden pond must be properly planted and cared for
If you want the water in your garden pond to be of good quality over the long term, you have to plant the pond correctly and, above all, maintain it properly and regularly.
Many underwater plants ensure that algae do not get out of hand, for example frog bites (Hydrocharis morsus-ranae), milfoil (Myriophyllum) or crab claws (Stratiotes aloides). These plants take their nutrients from the water and therefore compete with the algae. They also enrich the water with oxygen.
Care consists primarily of careful observation and then manual labor: If parts of the plant have been blown or fallen into the garden pond, they are fished out with a landing net or telescopic scissors; . B. carefully fished out with a rake.
Since the nutrient-rich deposits increase over time, which can hardly be prevented, you should occasionally remove these deposits with a pond sludge vacuum. If the pond is small enough, it is best to cover it with a net in autumn, then no leaves can fall into the water during the entire winter and you save yourself a lot of cleaning work.
If you do all of these, you will be able to keep your pond in good balance under normal conditions. Unless you want to put fish in it, that makes the whole thing a lot more difficult:
Be careful with fish in the mini pond
If you plan to create a very small pond, you should probably realize in advance that it would be better to avoid fish in the pond.
Because the fish have a powerful influence on the biological balance in the garden pond, and not necessarily in a positive sense: Excessive algae growth in the garden pond is promoted by an excess of nutrients in the pond water, especially by a high phosphate content, and fish droppings and unused Food is the most common source of phosphate that really clogs pond water. Maintaining good water quality in a fish-filled garden pond therefore requires very careful and regular maintenance. If you do not only use so few fish that they can take care of themselves in the pond, you will hardly get along without a filter system.
When to fight the thread algae in the garden pond
If the different types of algae in the garden pond can benefit from a too high nutrient concentration in the water for the various reasons indicated above, your power of observation is required: As soon as the algae growth suddenly increases, the equilibrium in the garden pond is in danger if you do not intervene in time The following:
If the phosphate content in the water is too high (over 0.035 milligrams per liter), the algae first multiply – at an increased speed – “peacefully”, if then there is a little more solar radiation and the water temperature increases a little, they multiply explosively, this is called an algal bloom.
An algae bloom of the thread algae then very quickly means that you no longer have to worry about whether the water is still okay or already too cloudy – it becomes unmistakably muddy cloudy, and next the algae then die off and decompose, the oxygen concentration in the pond drops, the fish suffocate and the whole pond “tips over”.
Fight thread algae
Before that happens, you need to take urgent action, precisely when you notice that the thread algae are increasing in the garden pond. Then nutrients have to be extracted from the pond water, and this works quite well even without technology and chemistry, if you have been attentive enough.
First of all, you simply take some of the thread algae out of the garden pond, in this way you also remove a large part of the pollutants that the thread algae has collected. Then you should give your aquatic plants a strong pruning, because they have already bound many of the superfluous nutrients during their growth, these are now removed from the water-nutrient cycle by the pruning. The aquatic plants can only continue to grow unhindered and bind nutrients again. Incidentally, aquatic plants and fished algae can be composted excellently.
If that is not enough, your garden pond needs a so-called renovation, which removes a lot of nutrients from the water. Here you remove the entire soil layer from rotten plants and replace the old pond soil with new, nutrient-poor soil. The aquatic plants are all cut back vigorously at the same time and maybe also divided, then you put them in the new pond soil and fill up with new water, as a rule you now have your peace of mind.
Conclusion
If you would like to be as relaxed as possible with the new piece of nature in your garden, it is best to lay out your garden pond in such a way that a biological balance is established by itself. So you will only have to fight thread algae or other algae in the garden pond in exceptional cases, but this is then quite uncomplicated and without great effort. And above all, with such a garden pond you do not have to enroll for a degree in water chemistry or hydraulic engineering in order to maintain an always clear water with a lot of technology or to check the suitability of algae-degrading rock granules, bio-adequate algae killer, Dr. Neptuns Teichklar or the new Biowunder filter system.
