Harper's Outdoor Book for Boys. Joseph H. Adams
about the aquarium allow it to stand for at least a week, in which time the putty and varnish will harden.
At a paint store purchase some marine paint, also known as “copper paint,” and give the wood-work two or three thin successive coats, allowing it to dry for a few days between each coat. Scrape the paint from the glass where it may have been smeared, and the complete aquarium is ready for water and stock.
Another way in which to construct the framework is to take a curtain-pole one and a half inches in diameter, and at a planing-mill have a quarter section sawed out, as shown at Fig. 17, so that an end rim will appear as shown at B. The part of the wood-work the buzz-saw cuts away will correspond with the grooves cut in the square sticks.
Four holes one and a half inches in diameter, or the same size as the stick, are bored half-way-through the bottom-board of the aquarium and V-shaped channels are cut in the board connecting the holes (Fig. 18). The wood-work is treated in a manner similar to that already described, and the corner-posts are held in place by long brass screws driven up through the bottom and into the lower ends of the posts. The top rail is made the same as shown in Fig. 15 C, and the glass is set as described. At the corner-posts the lap is well smeared with asphaltum varnish and putty and the angle strips are screwed fast to the posts as indicated at A in Fig. 17. While this is somewhat easier to make it is not quite so substantial for large tanks as the square post and channels.
When catching the stock for the aquarium it is best to use a drop-net. This is made of two iron hoops fifteen or twenty inches in diameter and held one below the other with cord as shown at Fig. 19. Mosquito-netting is drawn across the lower hoop and sewed fast; then a band of it is sewed about both hoops to close in the sides, to form a cylinder open at the top only. Some bait is placed in the bottom of the net, and then it is lowered into the water so that the top hoop drops down and the whole net lies flat on the bottom of a pond. When a number of fish are around the bait a quick haul will raise the upper ring; then pull the net up with the fish captives within the cylinder. You can quickly select the ones you want, and these may be placed in a pail partly filled with water.
For turtles, crawfish, and lizards a scap-net will be necessary. This may be made from stout wire, a broom-handle, and some netting. The ring may be almost any size, from six to twelve inches in diameter, the ends being sharpened with a file and turned so that they may be driven into the end of the stick, which should first be bound with wire to prevent it from splitting. The bag of mosquito-netting is made on the hoop and sewed fast, as shown at Fig. 20. When changing the water in the aquarium it is not necessary to empty it all out. A siphon made of a small rubber tube will answer very well to drain off a portion. The part of the tube in the tank should be held close to the bottom so as to suck up any dirt or sediment that may be there. Good ventilation, light, healthy aquatic plants, clean sand, and a proper proportion of fish to the volume of water are absolutely necessary to the successful aquarium. A few tadpoles and snails are advantageous in an aquarium, as they consume decaying vegetable matter and help to prevent the formation of algæ on the glass.
For the aquarium large enough to contain them, some artificial rockeries may be made from cement, gravel, and stones, as shown in the illustrations of the concrete rockeries Figs. 21 and 22. They should be made with openings beneath for the fish to swim through, and pockets should be made at the top to hold sand and the roots of aquatic plants. The rockeries should have a good flat base so as to rest securely on the bottom of the aquarium. Always have plenty of pebbles and river-sand at the bottom of the aquarium to make the fishes feel at home.
How to Manage an Aquarium
It is generally supposed that it is necessary to change the water in an aquarium at least once a day; but that is not the case. The true principle on which an aquarium should be conducted is not to change the water at all, but so to aërate and refresh the original supply as to maintain it always in a pure and perfect state. There are several means by which this may be done. The healthy growth of plants is very important, and active and brisk contact with the air of the atmosphere will greatly freshen the water. Motion in the water is absolutely necessary. In large aquaria this is obtained by an arrangement of tanks into which the water is pumped, and from which it flows rapidly, circulating through the tanks where the fish live. In its passage through the air it absorbs considerable oxygen, without which no fish can live. Fish placed in water that has been boiled die in a very few minutes.
The first thing to be done in the formation of a fresh-water aquarium is to start your plants in proper soil at the bottom of your tank, fill the tank with water, and leave it undisturbed until the plants begin to grow and the little bubbles of oxygen are to be seen rising to the surface of the water.
Choose your plants from such as you may collect from rivers or brooks or ponds anywhere in the country. Plant them, and then cover the surface of the soil with pebbles and small bits of rock, or anything that is suitable and in keeping with the rest of your arrangements. Never put sea-shells into a fresh-water aquarium.
Now fill your tank with water poured through a siphon or funnel, being very careful not to disturb the soil or the roots of the plants. You should have some clean river-sand in the bottom of your tank, and your pieces of rock should be so arranged as to form little caves and hiding-places for your fish. It will take perhaps two weeks to get your tank into a proper condition for fish to live in. Every bit of dead or decaying vegetation should be carefully removed. Keep your tank shaded from the heat of the sun, and expose it to the bright light only once in a while.
In order to manage your aquarium properly you will require a few simple tools. A little hand-net that can be bought for a few cents, or made for even less out of a bit of wire and a small piece of mosquito-netting, is useful for catching the fish or shells without putting your hands into the water. A pair of wooden forceps, like a glove-stretcher, will be found most convenient for nipping off bits of decaying plants or for catching objects that may have accidentally fallen into the water. Glass tubes of various sizes are also useful. If you want to catch any small object in the water with the tube, place the tube in the water with your finger over the hole in the top. Until your finger is removed the tube will remain full of air. Place it over the bit of refuse or whatever it is you want to catch, remove your finger, and the water will rush in, carrying the object with it into the tube, which should then be closed at the upper end by placing your finger over it as before. A glass or hard-rubber syringe is necessary with which to aërate the water thoroughly at least once a day, and oftener if possible. Fill the syringe, hold it high above the tank, and then squirt the water back again.
If a green film begins to gather on the side of the tank that is most exposed to the light, it should be cleaned away every day, and the sides of the glass polished carefully. A small piece of clean sponge tied on the end of a stick will answer the purpose very well, and, if used daily, you can keep the glass clear with very little trouble; but if the scum is neglected and left to accumulate, you will find it almost impossible to remove it from the glass even by hard scouring.
It is best to have only small fish in your aquarium, and for this reason trout are not desirable. Although very beautiful and intelligent, they grow so rapidly that they are likely to become in a short time too unwieldy for your tank. Goldfish and minnows are very good, and the common little sunfish or “pumpkin-seed” is excellent.
You must keep careful watch over the fish in your aquarium, and if any one of them appears to be sick he should be removed at once, very gently, with the hand-net, and placed in fresh water, where he will often recover. If, however, the little sufferer is doomed to die, it is better not to run the risk of his doing so among his healthy companions. It is best always to have a hospital for your sickly pets, and as soon as one of them, whether a fish or a bird or any animal, shows signs of ill health, he should be taken away from the others and placed by himself.
Certain varieties of snails live well in fresh water, and will be found useful in clearing away the green film that is almost certain to collect on the side of the glass; but you must be careful or they will devour your plants as well; and if your tank is very small it is hardly worth while to try