The foundation of any functioning aquarium
Aquatic plants in their natural habitat
In their natural environment – the streams, ponds and swamps of the tropics – aquatic plants rarely grow evenly, but instead tend to be scattered about in groups of varying sizes. These groups generally mark the site of so-called nutrient seepage springs. These are places where nutrient- and CO2-rich water streams slowly but steadily out of the ground. The ground in these areas is very fine-grained, dense and rich in humus. The reddish-brown coverings on the roots of the plants testify to the high iron content of the water.
Humus bacteria play a particularly important role here: with the help of the humus substances that are produced, they convert mineral nutrients into a form that the plants are able to absorb. Thus, in the tropics, plants will only grow on bare surfaces – for example the edges of newly-constructed roads – if a humus layer, even just a millimetre thick, has formed there. In the natural habitats of popular aquarium plants such as Cryptocorynes and Echinodorus, the ground is always very rich in humus.