Ceratophyllum Demersum, better known as Coarse Hornleaf, is an excellent oxygen plant often used in ponds. These plants have a huge advantage over algae. This is because Ceratophyllum Demersum has a very unusual way of growing. This oxygen plant can "stretch" its own cells, so to speak. This allows the plant to grow up to 10 centimetres a day. Since they grow so fast, they can absorb more nutrients and introduce much more oxygen. As a result, algae therefore have less of a chance of turning your pond green.
However, that is not the only advantage this plant has; through a special cooperation (symbiosis) between the pond plant and special micro-organisms, it ensures that all substances are removed from the water as much as possible, which results in higher clarity. The property that makes symbiosis possible is also known as allelopathic ability or allelopathy. Coarse Hornleaf additionally floats in the water, competing over sunlight with the floating algae.
Besides Coarse Hornleaf, Fine Hornleaf (Ceratophyllum Submersum) is also available from us. In terms of growth and competition over algae, Fine Hornleaf is certainly not inferior to the coarse species. More information can be found here.
Coarse Hornleaf is a dark green plant (Unlike fine hornleaf, which is slightly reddish) that does not produce roots and can reach a maximum length of up to 2 metres. The leaves are up to 3 centimetres and look something like the appearance of a simple feather. Be careful though, as this plant may look strong, but it breaks easily as it is very brittle. A notable feature of the hornwort species is that this oxygen plant goes into a kind of "hibernation". In fact, in autumn they make overwintering buds. These buds go to the bottom of the pond and hibernate there until the temperature permits and is warm enough, the buds detach from the bottom and grow again near the water surface into new plants. This pond plant also bears fruit. These fruits are small, olive green and have 2 to 3 curved spines.
In the Netherlands, Coarse Hornleaf is also found in the wild. This plant does not have many water quality requirements, which means it can grow in almost any kind of water. This is also good news for the pond, as it means the water quality is less critical. Incidentally, hornwort does like somewhat harder water.
The same rule of thumb actually applies to this oxygen plant as to other oxygen plants; 4-5 bunches per cubic metre of pond water are recommended. In this way, you will achieve the best results in terms of competition with algae and clear water.
Would you like to know exactly how many oxygen plants in pond needed based on the number of litres of water? Then use our handy Groves Calculator
Looking for high quality Ceratophyllum Demersum? Click the button to buy beautiful bunches of Ceratophyllum Demersum and other oxygen plants!
For a wide range of oxygen plants, visit the website Vijvermeester.nl.
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