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Balanced Aquarium and the Snailery — Part 2

The Pond Snails (Physa), one of the best kinds for the aquarium, will mow the conferva from the sides of the tank and will breed there, undisturbed, though fishes prey upon them.

The Trumpet Snail (Planorbis), coiled flat like a watch spring, a far lustier fellow, may be found in ponds and ditches.

Lymnaea is the name of several pond snails, whose dark, handsome shells coil to the right. They are inactive, a contrast to the ambitious, left-handed Physas.

Paludina, the marsh snail, may be represented sparingly.

Clams will live quietly in the aquarium, travelling about when they feel like it, ploughing with extended foot through the gravel.

Fishes, tadpoles and the little acrobatic Water Newt (Triton) live happily with the snails and clams, if fed regularly. Sticklebacks will build nests and hatch their young. Avoid fish over three inches long.

Crayfish are best kept in separate jars; they are beasts of prey and disturbers of the peace, attacking the fish and uprooting the plants. With bits of rock they build caves in which to hide.

Small bits of meat will be eaten by crayfishes and tadpoles. Insects, including "wigglers" from a neglected rain barrel (mosquito larvae) will be eaten by the fishes. They will pick up bread crumbs. Small creatures we overlook entirely furnish food for larger animals.

Jars containing four or five gallons of water should maintain three or four fishes, two to three inches long, with four or five newts, three or four small tadpoles, six or eight snails and two or three clams. One or two plants extending their tops up out of the water will be appreciated by the newts, which like to take a breath of fresh air occasionally. Snails, too, and tadpoles, enjoy this chance of a change.

Stocking the Marine Aquarium.--First cover the bottom of the tank with an inch of cleaned beach gravel. Pebbles of various sizes add to the beauty of this foundation and offer lodgment for anemones. Fill with the purest sea water obtainable.

Sea lettuce (Ulva latissima) is the most desirable plant for the marine aquarium. Collect from tide pools on the beach bits of shell and rock fragments to which are attached young plants of it. Arrange them on the foundation of sand. Broad bands of this plant may be floated on bits of cork at the surface, and anchored at the bottom for a green background against which to see the animal life to best advantage.

Solieria chordalis has brilliant, crimson, wiry branches in profuse bunches, a beautiful contrast to the cool green Ulva. It grows on rocks and shells at a few fathoms depth.

Grenella Americana, with narrow red ribbons, is a good plant, if young specimens are used.

Many beautiful seaweeds have proved to be harmful in the aquarium. Those named above are perfectly safe. Aeration is accomplished by green plants,--so the Ulva is our dependence for oxygen supply. Let the aquarium with its plants have a few days' rest before putting in the animal life.

Corals, even tropical kinds, live comfortably in the balanced aquarium for years. A cold water species is to be had in Long Island Sound and on the Jersey coast about Long Branch.

Oysters, mussels and clams live comfortably in the sand and gravel. Sea anemones "blossom," attached to stones and shells; they are among the greatest attractions of the aquarium.

The Tube Worm (Cistenides), in its sandy horn, and Serpula, in its twisted limy tube, do well. The Ship Worm (Teredo), in a fragment of honeycombed wood, thrives in the company above described.

Botryllus is a coloured, gelatinous mass, with a star-like arrangement of the individual zooids, which looks somewhat like coral. It is found attached to eel-grass and to wharf piles.

Sea Squirts are globular, gelatinous creatures that send out a jet of water when disturbed. They will live and multiply in the aquarium.

Snails of the periwinkle group (Littorina) are scavengers. They eat decayed vegetable matter, and pick up the crumbs dropped by fishes. The Dog Whelk (Nassa trivittata) helps at this job of cleaning, and he is an ornament to the tank. But he may drill a hole in the shell, and suck the life blood of your favourite bivalve, reminding you that he prefers fresh to stale food. Beware the Whelk (Buccinum), the Moon Shell (Natica), and the Drill (Urosalpinx), for they will slay without mercy every bivalve you put within their reach.

Hydroids, microscopic creatures of exceeding beauty of form, often mistaken for delicate seaweeds, occur in the aquarium as if spontaneously, attached to the glass sides or to objects inside.

Hermit and horse-shoe crabs, prawns and little blue crabs should be kept in separate jars. They are most interesting and beautiful. But they are too hungry and too selfish to share the quarters of better-mannered creatures.