Elodea the Dark (Egeria densa)
Elodea is dark, this unpretentious perennial, rapidly growing and developing different climatic conditions of the plant is often called the Brazilian Elodea, the taxonomic name Egeria densa. It is so unpretentious that it is considered an aquatic weed and even inexperienced fish farmers will be able to grow it in an aquarium.
In nature, Elodea dark grows in the natural South American warm ponds of Brazil, Uruguay, and Argentina. Due to its rapid growth, it is considered an aquatic weed, and it quickly spread through the water bodies of other continents. Elodea clogs actively exploited freshwater paths, behaves aggressively towards local plants in the territories of its expansion, and impedes spawning of fish.
The Brazilian Elodea was first brought to Russia in 1882, it was planted as a green ornament in artificial ponds and ponds of the botanical garden of St. Petersburg. Over the next year, on all nearby local rivers and ponds, green islands appeared from large stems of the aggressive invader Elodea. Soon he could be found in Siberian lakes and rivers right up to Lake Baikal. It is precisely because of their ability to spread quickly over the water that the Elodea is called the "water plague."
Freshwater Elodea is dark or Brazilian, spectacular and attractive in appearance, resembles a dark green Christmas tree. It grows immersed in ponds and lakes, streams and ditches with a slow course, forming thickets either at the bottom or in the water column.
She has small, lanceolate leaves, slightly elongated with pointed teeth along the edge of the leaf blade translucent. The leaves are attached up to 1 cm long and up to 0.5 cm wide, 3-4 in one whorl directly to the stem. On the tops of the stems, the leaves are light, below they have a juicy green color, in good light they acquire a reddish color.
On the dioecious plant of Brazilian Elodea, flowers of different sexes are formed, male ones with 9 stamens, female ones with 3 carpels. The stems of dark elodea in nature can reach a length of 1.8 m and grow to a depth of 6 meters. In aquariums, its stems reach 70 cm. Dark Elodea blooms with small white flowers. But in the aquarium, flowering dark Elodea is almost impossible to see, because most of the plants from plants sold to aquarists are male, reproducing vegetatively.
In the aquarium, Elodea Brazilian can only reproduce vegetatively. To do this, you need to choose a healthy floating shoot with a length of 15-25 cm and place it in the conditions when white strings of young roots appear on it. A layer of river sand of 2-3 cm is poured at the bottom of the aquarium tank, an elodea process is planted and deepened. Soil quality for this unpretentious plant does not matter. After a short period of adaptation, the elodea will quickly grow.
Brazilian Elodea does not like warm water and quickly dies at temperatures above + 25 ° C. She needs a large aquarium with cool water. The optimum temperatures for its cultivation will be + 16 ° C - + 22 ° C. The acidity and hardness of the water for growing dark elodea is not significant, but it is better if they are pH 5.0 - 8.0, KH 2-12 °.
But Elodea the dark is demanding on illumination, devices should be of a power of 0.5 - 1 W / l, lighting is selected taking into account the location of the tank and neighboring plants. The minimum duration of the backlight will be 10 hours, better longer. The backlight should be organized so that the rays of light reach the lower leaves so that they do not decay. When the content temperature drops to + 4 ° C, the Brazilian Elodea “falls asleep”, but with an increase in temperature, young shoots appear again in place of the sleeping kidneys.