MAKING OUR HOME BEAUTIFUL 219
end of the small tank, or have two or three depressions if the tank is larger. These not only add diversity to the appearance, but the fecal matter of the fishes, surplus food, and other wastes will collect in the depressions and can be more readily siphoned off.
The plants can be anchored by packing their roots in the sand or gravel, and, if necessary, large pebbles can be placed about the bases of the plants until they become firmly rooted, or the lower end of the stem may be weighted by wrapping with a small piece of soft lead just above the roots. Some aquarists insist that a layer of soil should first be placed under the gravel, but with completely aquatic plants this is quite unnecessary, while the soil is often a source of danger to the animal life through the decomposition of its organic ingredients.
If the aquarium is to support its full quota of animal life, the plants must be thickly placed. In fact, there can hardly be too much vegetation so long as the fishes have sufficient room to swim about. The plants tend to mass at the top of the aquarium, leaving free space below for the fishes.
To obtain the best results, the aquarium should be planted at least a few days before the animals are introduced. This allows the plants a better opportunity for taking hold of the sand, and it also permits them to thoroughly aerate the water in preparation for the animal life.
In order to prevent the possible introduction of parasites into the aquarium along with the plants, it is well to sterilize the latter before placing them in the tank. This can be done by immersing the plants for ten or fifteen minutes in a solution of creolin—two teaspoonfuls to the gallon of water. The plants should be well rinsed in water before they are placed in the aquarium. Phenol sodique solution—a tablespoonful to a quart of water—is also highly recommended. The plants should be allowed to remain in this solution for several hours and should, of course, be thoroughly rinsed after removal from the antiseptic bath.
The plants available for aquarium purposes are entirely too numerous to mention here. There are many native species,