Keeping & Caring
Keeping and caring for rainbowfishes in captivity is relatively simple as far as general aquarium conditions are concerned - they are one of the easiest fishes to maintain. Nevertheless, rainbowfishes do have a number of basic requirements in order to survive from day to day, to breed and to maintain populations over the longer term. They require suitable habitat, proper nutrition, and a stress-free existence if they are to grow and remain healthy.
If you want to be successful at keeping rainbowfishes then you must make an effort to learn some basic aquarium principles to maintain and care for them. More than a few fishkeepers have watched the inhabitants of an unhealthy aquarium die because they had failed to learn the basics. If you do not have time to learn the basics, then I suggest that you seriously reconsider the idea of keeping rainbowfishes in captivity. Practical experience can only be gained through time and exposure to the aquarium environment. It’s a combination of learning aquarium disciplines and experience that will make you a successful aquarist. The actual learning that is required is relatively easy and the rewards so much greater.
Rainbowfishes are physiologically well adapted to specific ecological niches, defined by the physical, chemical and biological parameters of the water in which they normally live, with preference and tolerance limits for temperature, salinity, pH, dissolved oxygen, organic and inorganic substances, light, etc. Conditions outside the optimal preference or tolerance ranges may result in distress, impaired health and mortality, all of which are often associated with improper rearing conditions that cause poor water quality. Thus, careful observation of the fishes behaviour and water quality is required to maintain optimal conditions for health and welfare.
In order to design more natural aquarium environments it is essential to have a broad understanding of the biology and ecology of the fish species in question and especially the environment that the species inhabits. A feature of any pristine environment is the huge variety of habitats that are available. Few species of rainbowfishes flourish in bare, barren habitats. Habitat is provided by rocks, logs, fallen branches, aquatic and riparian vegetation. However, many aquarium environments are completely devoid of structure. They are usually featureless, monotonic enclosure with no opportunity for the inhabitants to display any natural behaviour. They bear no resemblance whatsoever to the fish’s natural environment and densities can be up to 100 times greater than those in nature. Reductions in density alone seem to have mixed results but it appears that intermediate densities will produce better quality fish.
Simple measures like increasing filter performance, providing dark backgrounds, natural substrate material, submerged structures, such as driftwood, and floating plant cover could improve the aquarium environment. This also leads to lower levels of aggression, better health and improved growth rates. Aquarium-reared rainbowfishes that spend some time in outside ponds improves growth, colour and survival rates substantially.
In the pond environment the fish are not only exposed to natural temperature and light fluctuations, they also have access to a range of naturally occurring live foods.
Successful set-ups can range from a standard 55-litre aquarium with a modest box filter costing very little, to a huge 650-litre aquarium with elaborate trickle filtration, carbon dioxide injection and computer operated lighting systems. Some hobbyists believe that the more expensive the life support system is, the better their success will be. However, all aquariums despite how simple or how specialised, share the same principles for maintaining rainbowfishes successfully.
When choosing an aquarium the largest size one can afford is usually recommended. However, any size aquarium can be successfully maintained, although aquariums smaller than 55 litres are not worth considering. The problem with small aquariums is that the environment can degrade so rapidly that the hobbyist is unable to solve the problem in time to save the inhabitants. The small 55-litre aquarium is often the most popular size with beginning hobbyists because of its moderately low price. However, problems start when they assume that this size aquarium can do more than is realistically possible.
Rainbowfishes are mid-water to surface swimming fish and require sufficient space to swim. They are also highly social and form schools for most of the time. It is obvious, therefore, that the shape of the aquarium in which rainbowfishes are kept is of great importance to them. In a small aquarium, they will feel stressed, resulting in health problems. The actual surface area of an aquarium is more important than depth. The depth of the aquarium is of no importance, except that it should never be so shallow nor so deep that the aquatic plants fail to grow properly.
An aquarium depth for rainbowfishes may be anything from 30 cm to 60 cm, in proportion to its superficies. Aquarium width should be at least 45 cm, particularly for the larger species. Rainbowfishes can jump, and it is therefore important to keep the aquarium covered at all times. Covers should be made of clear plastic or glass and fit tightly because rainbowfishes can escape through even relatively small slits. It is advisable to use extra strong tape to secure one end of the lid to the aquarium.