The Egeria najas waterweed is a fast-growing plant for the aquarium that is also relatively easy to cultivate. Its name already reveals that it belongs to the family of the waterweed and is therefore related, among other things, to the dense leaved waterweed
In addition, there is a risk of confusion with other plants, so that it is not so easy to describe the mermaid-like waterweed aptly.
Egeria najas grows quickly and has hardly any demands on the ambient conditions, so it is suitable for almost all aquariums. Fish enjoy a dense population, the water quality remains stable.
Due to its rapid growth, Egeria najas removes many pollutants from the water, which benefits the underwater biotope. Thus the stem plant is also a natural competitor for unpleasant algae. The plant only needs a lot of light for healthy growth, otherwise it adapts flexibly to the water values. It tolerates temperatures up to 28 ° C and can be used well in tropical basins. Caution is advised with perch and other herbivores, as they attack the narrow leaves.
Egeria najas: Quick facts
Scientific name: Egeria najas
Trade name: Paraguayan waterweed
Natural occurrence: Lago San Bernardino, Paraguay
Height: up to 50cm in length
Optimal temperature range: 10-28 ° C
Leaf color: light green, stems yellowish
Propagation: head cuttings. Side shoots then form, which can be removed when they are about 20 cm long
Use: Najas is the ideal hiding plant for young fish. This waterweed is often used in ornamental fish farming
Light requirement: the more light, the closer the leaf whorls are.
Special features: Also suitable for the garden pond in summer
Scope of delivery: Bundle with 6-8 stems
Difficulty: easy to care for
Light requirement: lots of light
Occurrence: South America
Location in the aquarium: middle ground and background
Aquarium type: cold water aquarium
Egeria najas: Natural Habitat
Egeria najas is an undemanding waterweed species, but not quite as well known as the dense leaved waterweed, Egeria densa. Like this one, it comes from southern South America (Argentina, Uruguay, Paraguay, Brazil), but is widespread even further north into the tropical zone.
This real underwater plant is found there in flowing and standing water. The leaves of Egeria najas are narrower than those of Egeria densa and have clearly visible teeth on the edge. This makes the plant look more delicate. The very densely leafy shoots are usually around 2 to 3 mm wide.
The mermaid-like or Paraguay waterweed is an adaptable and fast-growing aquarium plant, but should be illuminated at least to a medium level. Nutrient-rich water is very beneficial for their growth, CO2 fertilization is not absolutely necessary.
You can let it float on the surface or plant it in the ground, where it is anchored with a few long, unbranched roots. Temperatures between 15 and 26 ° C are optimal, and 30 ° C is still tolerated, at least temporarily.
Egeria najas is somewhat more suitable for tropical aquariums than E. densa. Like other stem plants, it is easy to propagate by cuttings.
This waterweed from the tropics and subtropics can be used in many ways, especially for the initial planting of newly established aquariums. It makes itself useful in breeding tanks by producing a lot of oxygen, absorbing excess nutrients and providing hiding places. But their deep green, densely leafed shoots also look decorative in variously planted, rather high aquariums.
Egeria najas: Characteristics
The Egeria najas and the dense-leaved waterweed are both stem plants. The similarity between the two plants goes much further: the stems of both plants are covered with small elongated leaves.
- In the Egeria najas, however, the leaflets are usually a bit finer than in the dense-leaved waterweed.
- In addition, one can usually make an interesting observation regarding the leaf edge of the Egeria najas waterweed: This is very clearly jagged and gives the plant more liveliness.
On the basis of the size of the individual stems, however, one cannot distinguish the Egeria najas waterweed from the dense-leaved waterweed: These can become extremely long in both plants in the aquarium, but at the same time they remain quite narrow in both cases at a few centimeters. The latter is also the reason why you will not bring in a single stalk of the Egeria najas waterweed in an aquarium, but several and prefer to plant them in a group.
Because of its resemblance to the dense-leaved waterweed, it is advised that you should carefully determine the species.
Egeria najas: In the aquarium
The Egeria najas, like the dense-leaved waterweed, should be a plant for the aquarium that even beginners can cultivate.
- Make sure that the there is enough lighting in the aquarium.
- The nutrient levels in the aquarium should always be at an optimal level.
- If you have a small aquarium, you have to make sure you prune the Egeria najas on a regular basis so that it does not overgrow the entire aquarium.
Egeria najas: Positive effects on the aquarium
- The rapid growth of the plant can make an important contribution to stabilizing the water values and thus also protect against excessive algae infestation in the aquarium.
- The plant uses away a lot of nutrients and thus deprives algae of the basis of life.
Spreading growth also means that the plant in the aquarium will develop many head cuttings and side shoots. These can be used for reproduction. This means that you do not need to spend any more money on vegetation.
The Egeria najas can be used both in a fairly warm aquarium, which has temperatures of around 26 degrees, and in an aquarium, in which the temperatures are very low, around 15 degrees.
Egeria najas: Placement in the aquarium
Because the Egeria najas grows very fast and tall, you should place the plant in the back of the aquarium tank.
If placed further up front, it might restrict the view into the aquarium too quickly.
Even when placed in the background, the Egeria najas has to be trimmed often so that it retains the desired shape and does not get out of hand.
It provides great hiding places and spawning grounds for fish because it offers a lot of options to create dense greenery in the aquarium. This is especially useful for breeding tanks.
Take care when planting the Egeria najas waterweed. You should not treat the individual stems too roughly as they are prone to break.
If you want to save yourself planting in the aquarium, you could also consider using the Egeria najas as a floating plant – at least this is a variant of use that is often found with the related leaflet waterweed.