Biological balance is the basis of a good relationship between living organisms. The aquarium hobby is mostly interested in the keeping of fish in indoor aquariums, but since the lives of fish are closely interwoven with the lives of the plants, aquatic vegetation is an integral part of aquarium science.
Plants are the basis of life on earth. They are producers, the only organisms able to develop organic substances from inorganic mineral elements and their compounds. All animals are consumers, their bodies being unable to utilize inorganic substances directly. The basic food of herbivores is plants, so even the largest carnivorous animals are indirectly dependent on plants. In addition, plants are the greatest single source of oxygen in the atmosphere. Without oxygen animal life on earth would not be possible.
The secret of the remarkable production by plants of both oxygen and organic food substances is of course photosynthesis. During the day the plant consumes nutrients (mineral substances) and obtains carbon dioxide from the atmosphere or from the water, where it has been released as a by-product of animal respiration. In the presence of sunlight and the complex compound chlorophyll, starches and sugars are produced and oxygen eliminated as a waste material. At night the plants reverse their role, breathing in oxygen and eliminating carbon dioxide, but during this time most fish are inactive and their need for oxygen is minimal.
It is not our intention to discuss the details of these fundamental functions of plants and their importance to the aquarium. These are matters well known to everybody, with the details easily available in any basic biology book. We wish to deal first with other principles of aquarium keeping commonly used and readily understood by the aquarist, and then with the cultivation of aquatic plants and their use in the aquarium.
Leafy plants are very useful for the spawning of egg-scattering fish like these tetras (Hyphe&sobrycon species). Those eggs caught among the leaves of the plant usually escape prédation by the parent fish. Photo by R. Zukal.
In passing it might be mentioned that many of the aquarium plants described in the following pages are actually amphibious, growing both in and out of the water. If they are carefully watered once a week (even less with some species) they can also be used as potted plants outside the aquarium. The shiny green leaves and often bright infloresences of Cryptocoryne are certainly as attractive in the living room as in the aquarium.
Our main goal in writing this book has been to acquaint readers with the practical and, to some extent, theoretical aspects necessary for the choice and cultivation of water plants. If our readers are successful in cultivating even one or two of the more exacting species, we will be satisfied.
Was this article helpful?