Stocking Aquariums

Most hobbyists begin with several fish and invertebrate species that are of the same conditions on the water chemistry. Fish will eat most plants. For some species of fish the water levels also play a role. The mbuna, a cichlid endemic of Lake Malawi, will require rock structures that provide caves and retreats.

The rock pools where these species are maintained generally require a very good filtering system since nitrogen conversion is not supported by aquarium plants. As with the rock pools, the basin aquarium requires specific environmental conditions to prevail.

Fish are socialized and need a high velocity of water for their well-being. A strong centrifugal pump that has its exhaust port on one side of the basin and aspirates toward the other side of the basin achieves this. In large public aquariums one can see flumes, which are simulated streams, containing among other things, brown trout.

There are certain kinds of aquariums, mostly spread among experienced hobbyists who want to maintain some kind of target and possibly breed, that provide for species with special retaining requirements. An example of such species is the Australian wustengrundel who feels most comfortable during the night when the water temperature drops sharply in the aquarium. Few other fish species would cope over time with these large temperature fluctuations.

Other types, because of their aggressiveness towards other fish, are not suitable for a position in the community tank. For example, there is the tendency in freshwater or in brackish water aquariums for puffer fish, such as those represented by the durable assel, dwarf and Palembang puffer, to pull the fins of other fish. Under certain circumstances, at least the first two types can be kept together with a very agile species.

Biotope aquariums are aquariums in which conditions occurring in the wild habitat are modeled as accurately as possible. In such aquaria only fish from the same region are socialized.

Classically modeled habitats include a stream in the Amazon basin, an acidic pond in the Amazon basin, a Central American coast, Bach, a West African river, a Lake Tanganyika biotope, a rocky coast in Lake Malawi, a Southeast Asian creek, a Southeast Asian irrigation canal, a Southeast Asian river estuary (brackish water), and a river in Australia and New Guinea.

In the natural aquarium in Holland, the species of fish have a less than equal role to play as compared to the aquarium plant species. Occasionally, Dutch plant aquariums completely renounce the culture of fish. For both types of aquariums with carbon dioxide, fertilization is the rule in order to ensure optimal plant growth.