Basic Do's and Don'ts
Here are a few basic tips on keeping fish in an aquarium at home.
1. Keep the tank clean.
2. Don't overcrowd your aquarium.
3. Wash plants, sand and rocks first.
4. Don't change the water. Top up the tank with rainwater every so often.
5. Don't overfeed the fish.
6. Don't scare them by tapping on the glass.
7. Remove any sickly fish to prevent the spread of disease.
8. Read books to improve your knowledge, and seek advice from your local aquarist.
To be a success, the home aquarium must copy as nearly as possible the natural surroundings of its inhabitants. To do this, a few simple rules should be followed. First, the water must be kept fresh and aerated (it must contain enough air for the fish to breathe). This is assured by not overcrowding the aquarium, by including water plants, and if necessary by aerating the water by means of an air pump. Secondly, the inhabitants of the aquarium must be able to live together without fighting or eating each other. Thirdly, the animals must be kept clean and not overfed.
An aquarium should have as much as possible of its water surface in contact with the air. The goldfish bowl, with its narrow neck and curved sides, should not be used. The best home aquarium is a glass-sided tank, wide and broad but not too deep. It should have a glass cover over the top to reduce evaporation of water and to keep out dust... and cats. The cover must be raised slightly by fixing pieces of wood or cork at each corner of the tank.
The simplest way to start a home aquarium is to buy ordinary goldfish. Avoid the more exotic varieties until you have gained some experience. Start off by choosing healthy fish from a reputable aquarist. A healthy goldfish is lively and active, with erect fins and a well-rounded body. Goldfish are cold water fish so the tank does not need to be heated. However, tropical fish, admired for their brilliant colors, live in warm water and to keep them you will have to install an electric water heater in the tank. Never keep goldfish and tropical fish in the same tank.
A layer of sand or gravel, planted with water plants, makes the tank look more attractive and also greatly improves it as a fish habitat. Your local aquarist shop will help you choose the right plants. Probably the best plants for a beginner are Vallisneria, Sagittaria and Anacharis.
The plants in the aquarium help to aerate the water. They absorb, or soak up, the carbon dioxide gas passed out by the fishes. Out of this gas they extract the carbon and use it, with the aid of sunlight, to make their food. The oxygen from the carbon dioxide is then released into the water- in a well-lit aquarium you will see bubbles of oxygen rising from the plants. At night the plants absorb oxygen from the water as they breathe, so it is essential that the aquarium be well lit for about 12 hours a day. Remember too that the water will also take in oxygen from the air, and to some extent this makes up for the oxygen absorbed by the plants during the night. Some floating plants such as duckweed can also be put in the tank; fish will feed on this and it also provides shade for them.
For aquarium "housekeeping" you will need a wire brush or a flat metal scraper (a razor blade held in a piece of cane is useful) for cleaning the inside of the glass. Small plants (algae) will grow on the side which faces the light. Although they do no harm to the fish, they do make it difficult to see clearly into the tank. Freshwater snails, such as the ram's horn (Planorbis corneus) or the freshwater winkle (Paludina contecta), browse on algae and can be put into the tank to keep down this plant growth. However, the snails eat the eggs of some fishes, so they should be removed to a separate tank when the fish are breeding.
Other useful tools are a dip-tube siphon for removing waste debris from the bottom and a small hand net for handling the fish. Do not catch the fish with your hands as you will rub off their scales and protective slime, increasing the risk of disease. There are a range of mechanical aerators on the market, and it is a good idea to have a small floating thermometer in the tank. The water temperature should never rise above 13°C for a cold water aquarium. For tropical fish, the best average temperature is 24°C. To heat the tank, buy a thermostatically controlled electric immersion heater and seek expert advice on how to install it.