The theory of a balanced aquarium

The world as we know it is in balance. Animals breathe in oxygen and give off carbon dioxide. Plants absorb carbon dioxide and give off oxygen as part of there process of photosynthesis. Animals eat plants and the animal waste feeds plants. Water evaporated from the sea and comes back as rain to freshen the earth.

• The absolute balance of an aquarium world is not usually possible for a beginner. Usually the fish give off more waste matter - both in gas and solids - than plant life can absorb. And plants almost never provide sufficient food for fish life in an aquarium tank. Below are the things that the aquarist must provide to maintain plant life, but too much encourages the excess growth of algae, causing green water and green-coated tank walls.

• Food: it must be a balance of vegetable and animal matter - insufficient food stunts the growth and lowers the resistance of the fish to disease. Too much food can also harm the fish by polluting the aquarium.

• Size of tank: The tank must be large enough to provide space according to the number and size of the fish. It must have sufficient surface area so that oxygen can be absorbed to satisfy the fish.

• Temperature: The range of 24 degree centigrade to 30 degrees centigrade is ideal for most tropical fish.

• Gravel: One or two inches of sand gravel is required to anchor plants. Too much of gravel accumulates waste matter and tends to pollute the aquarium.