|Standard Cyclopedia of Horticulture|
Aquarium. The aquarium as here understood is a glass tank for live fish, plants, and the like, for the dwelling-house or other suitable place.
The aquarium should be in a place where it may receive light, but direct sunlight is not necessary; and to keep an aquarium in a healthy condition, living plants in the water are absolutely necessary and plants will not thrive in dark rooms; neither will fish retain then- bright coloring. The square or rectangular aquarium with open top affords a large breathing- space or air for the fish—which is another requisite, and the fish will be healthier and live longer than in a glass globe with small neck and orifice. Another and very important factor in the aquarium is sand and small pebbles. These should be washed clean of all soil before placing in the aquarium. About 2 inches over the bottom is sufficient. The plants should be planted before filling the aquarium with water. Figs. 285-287 show useful window aquaria.
An aquarium, to be in a healthy condition, should contain living plants-oxygenators—which are as necessary as food, as fish must have good air. The aquarium must be kept clean. The sediment should be removed from the bottom with a dip tube twice a week, and the inner side of the glass cleaned with a wiper once a week. Encourage the growth of the plants at all seasons; admit plenty of light, but no direct sunshine. There should also be a few tadpoles and snails in the aquarium. These are very essential, as they are scavengers, and devour the confervoid growth that frequently accumulates on the plants. In fall, give a thorough cleaning and rearrangement of the aquarium, so that all are in the best condition possible before winter sets in. In March it should be care fully looked over, and undesirable plants removed or transplanted. Additions may be made or any change if necessary.
Following are some of the best plants to place in the aquarium, all of which can be easily and cheaply procured from dealers who make a specialty of aquatics: Cabomba caroliniana (commonly called Washington- grass or fish-grass) is one of the very best oxygenators and a most desirable plant for the aquarium and can usually be had in quantity at any season, except late in winter. It is usually sold in bunches, but after winter sets in, bunches of cabomba will not remain long in a healthy condition in the aquarium without care and attention. Plants to be of benefit in the aquarium must be living, and before these bunches of grass can emit roots and be self-sustaining, the fish too often nibble and disturb them to such a degree that, instead of being serviceable to the aquarium, they are a positive injury. Elodea, or Anacharis (water pest): there are two forms of this useful plant. E. canadensis is a very rapid grower and may be found in ponds in dense masses. When once established, it is a pest and hard to eradicate; but being of stem growth, it is not so readily grown in the aquarium. The giant form is a very desirable and valuable plant and can be used to good advantage, making a very interesting as well as a valuable plant in the aquarium. Myriophyllum spicatum somewhat resembles the cabomba, but is of a darker color and stronger in growth and texture. It is a hardy plant and will withstand the winters in the neighborhood of Philadelphia. When cabomba is unattainable, this may be had in good condition. It is also an excellent plant to use for fish spawn during the breeding season. This must not be confused with the Myriophyllum proserpinacoindes, commonly called parrot's feather, as the latter is useless as an aquarium plant. Sagittaria natans is a very pretty strap-leaf variety of sagittaria and useful for a small aquarium. But S. sinensis, the giant form, is the best of all sagittarias for the aquarium, and is indispensable. When planted in the aquarium and allowed to get well rooted before the fish are introduced, it can be relied upon to maintain the aquarium in a healthy condition for several months. Vallisneria spiralis (eel-grass, tape-grass, wild celery) is a native plant inhabiting streams and rivers, and often used in the aquarium. Its long, narrow, strap-like blades or leaves are more flexible than the sagittaria and the tips float on the surface of the water. They are light green in color and of softer texture. It is a difficult plant to carry over winter, its natural propensity being to die down in winter, just the season when it is wanted in evidence in the aquarium. Ludvigia Mulerttii is one of the most conspicuous, ornamental and useful plants for the aquarium and is always great demand. It is much larger and a stronger grower than L. palustris of the middle and northern states. It is a native of the southern states, whence come our supplies in winter in small quantities and for high prices, the plants very unsatisfactory at best. The difficulty is that plants, or rather sprays, plucked from growing plants and shipped North, receive a violent check in the change of temperature and the closely confined condition of the packing- case. The result often is that the plants or sprays lose a great part of their foliage, and when afterward subjected to cold running water are completely ruined. The only safe way is to secure stock during the summer or early fall, getting plants established in pots before preparing the aquarium for winter. In this condition, the plants will hold their own and winter over; but to attempt to grow southern stock in winter in our northern states is futile. There are a few other submerged plants that might be used, but the above-mentioned are the best and the best oxygenators for large or small aquariums. Floating plants should be used sparingly in the aquarium, an open, clean surface being most desirable and even necessary for air. Moreover, the majority of the floating plants are suitable only for summer culture. Another reason why surface or floating plants do not succeed in a house aquarium is that the water is deficient of plant-food suitable for such plants. Plants that die in an aquarium would, if transferred to a tub containing a quantity of soil, as well as water, make rapid and healthy growth. Limnocharis Humboldtii (water poppy) is a plant often used in the aquarium. It is necessary to plant this in the sand in the same manner as other aquatic plants, although the leaves are floating, similar to the leaves of a pond-lily. Eichhornia crassipes major (water hyacinth) is a very desirable plant for catching the fish spawn, but under ordinary conditions lasts but a few days in the aquarium. Miniature plants of these are very pretty, and fish are very fond of nibbling at the roots to the detriment of the plants. These, with many other plants, are best adapted for the summer aquaria where they can enjoy the benefit of sunlight and open air.
Numerous free-floating plants are adapted to the aquarium, but too many must not be in evidence, or the fish may become suffocated. The azollas are very pretty, and the fish will occasionally eat the plants. The salvinia is another small plant often seen in the aquarium, but under favorable conditions it grows very rapidly, and forms a complete mat, which must be avoided. The European and American frog's-bits (Limnobium Spongia, Hydrocharis Morsus-ranae) are very attractive plants, their long, silky roots reaching down in the water.
In summer the plants and fish should be placed out- of-doors in a fountain basin, pool, or a tub sunken in the ground in a partially shaded place; and a fresh aquarium should be stocked in the fall.
Aquariums are rapidly increasing in popularity for home use, and are of great service in nature-study. A permanent aquarium need not be an expensive affair. The rectangular ones are best if large fishes are to be kept, but they are not essential. A simple homemade aquarium of glass and wood (Fig. 287) is described in Jackman's "Nature Study," as follows (the dimensions being slightly altered): "Use an inch board 11½ inches wide and 12 inches long for the bottom, and two boards of the same thickness and length, 10¾ inches high, for the ends. Three-eighths of an inch from the edge on either side, with a saw, make a groove ¼ inch deep and wide enough to receive loosely double- strength glass. Groove the end boards and fasten them to the bottom with screws, so that the grooves will exactly match. Partially fill the grooves with soft putty, or, better, aquarium cement, and press into each side a pane of glass. By making the bottom board 11½ inches long, an ordinary 10 x 12 window pane will be the proper size. When the glass is pressed to the bottom of the groove, draw the two ends in at the top until the glass is held firmly and then fasten them in place by narrow strips of wood, one on each side of the tank, placed on top of the glass and screwed to the end pieces. These strips also protect the hands from injury while working with the specimens in the aquarium. Before filling with water, the inner surface of the bottom and ends should be well rubbed with oil or paraffin and the grooves inside the glass well packed with putty." After the box is made it would be well to let it stand in water for a day or two. The wooden sides will swell and tighten the joints, and leakage will be less probable.