Feeding Tropical Fish

Newly bought fishes should not feed for a day after their arrival. They are usually too disturbed to eat, and if the food is not eaten it decomposes and pollutes the water.

After twenty-four hours, feed sparingly once a day. When the fishes have settled down and are eating regularly, start twice-a-day feedings. You should always feed your fish sparingly. You should not over feed the fishes. You should give no more dry food than can be consumed off the surface of the water in one and one-half to two minutes. Always leave the fishes hungry enough to search over the bottom for any food that may have dropped from the top.  The average fish’s stomach is the size of its eye. It can eat at o meal only about as much food as would cover one eye. Very few fishes can eat in the dark.

Very few fishes can eat in the dark. Never feed just before turning the lights off or immediately after turning them on. In the first case, the fishes need time to pick all the food off the bottom; in the latter case, it takes fishes ten or fifteen minutes to adjust to the light after having been in the dark for some time. By the time they have adjusted sufficiently to eat, the food will all have sunk to the bottom.

Signs of overfeeding are recognized as cotton puffs on the bottom and plants, as a gray slime over the bottom, as milky water, and as black gravel. As the particles of food are smaller than the granules of gravel, uneaten food works down into the gravel until it reaches the slate. Foods that are not eaten will lie at the bottom of the aquarium and rots, and as more and more waste food works down, the putrefaction spreads up toward the surface of the gravel.

People are frequently surprised when they stir up the gravel in their tanks and reveal what has been festering below an apparently clean surface. A light, occasional stirring of the gravel will help prevent this situation from developing. Best of all, prevent it by not overfeeding.

Aquarium Gravel

In practice it is entirely possible to keep fishes indefinitely in a bare aquarium. They do not require gravel, plants, rocks, or ornaments. But how many people would keep such an aquarium in a living room? An aquarium to be properly enjoyed should be a thing of beauty, a miniature underwater garden.

Gravel is used primarily as a rooting medium for the plants. A depth of 1 to 2 inches is usually sufficient. The greater the depth of the gravel, the greater the likelihood the water in the aquarium will be polluted. To avoid pollution, many aquarists put their plants in small pots which are set on the bare floor of the aquarium, even though this does not look as attractive as other plantings. When using this method, it is best to keep a thin layer of gravel, about 1- inch deep, over the aquarium bottom. This will “hold” settlings. It should be siphoned up and replaced with fresh gravel when cleaning the aquarium.

Crushed rock, preferably containing no lime, is best. To test for lime, drip some hydrochloric acid on the grave if it fizzes, lime is present. Medium grade #2 or #3 gravel is most satisfactory. The size of the granules should be about twice the size of a pin head.

Plants do not grow so well in fine gravel as in coarse; but if the gravel is too coarse, bits of food will drop into the spaces between the particles, where the fishes will not be able to get at them. So gravel size is important. Note: never use sand. Sand is so fine that there is very little circulation throughout. Putrefaction takes place very readily under such circumstances.

Do not try to wash too much at once: 3 to 6 pounds at a washing is enough. Place this amount in a large pot or bucket. While running faucet water on it, stir the gravel well; then pour off the dirty water. Repeat until no more dirt can be stirred up. Using a sieve or colander for washing gravel is often unsatisfactory. There is then no way of telling whether all the dirt has been washed out.

Some aquarists report good results from the use of layer of well-washed river mud below the gravel. The dangers of such a procedure far outweigh the possible benefits. Should organic matter be introduced in the mud, its decomposition will pollute the aquarium. The pH of the aquarium is frequently disturbed by the use of mud. Uprooting a plant by the aquarist or natural rooting by a Catfish can disturb the mud and result in a cloudy, messy tank.