A Beautiful Tropical Fish for a Small Aquarium - Its Appearance - The Best Form of Aquarium How to Rear and Feed the Young

Of all the tropical fish imported into this country for aquaria none can surpass, or even equal, in beauty of shape and colouring the Paradise fish from China.

Nor is its value as an inmate of an aquarium confined merely to its handsome appearance, for it is comparatively inexpensive, and as hardy, when properly cared for, as any other imported fish.

These fish cost from 3s. 6d. to 7s. 6d. each, and examples are nearly always on sale at the various dealers in such livestock.

The ground colour of this fish is a beautiful iridescent blue-green, barred vertically with reddish orange ; the top of the head and neck are very dark silver, speckled with blackish blue dots ; the long, flowing fins are orange, bordered with peacock blue. On each cheek of the male is an ultramarine spot, edged with bright orange ; the female shows this marking only in a faint outline. The sexes are readily distinguished thus, as well as by the longer fins of the male fish.

A Suitable Aquarium

The aquarium for Paradise fish need not be large ; one eighteen inches long and of proportionate depth and width will be very suitable for a pair of these fish. A large bell-shaped glass can be used, as owing to the small size of the inmates, the appearance of distortion is not so much in evidence as is usually the case when these vessels are used as aquaria.

Whichever pattern is adopted, some arrangements must be made whereby the temperature of the water is kept at about 650 Fahr. all the year round, excepting during the summer months, when it must be raised gradually to 850. This is best done by standing the aquarium in a tray or pan of water, which is placed upon a lidless box containing a small oil lamp or gas ring kept constantly burning. A layer of sand, nearly two inches deep, must cover the floor of the vessel for planting water-weeds, of which the Paradise fish require a greater amount than most other varieties of fish.

Valisneria is the best weed to use, and a sixpenny bunch will be required, the roots of the plants being weighted with stones and pushed down into the sand ; in addition plenty of duckweed should cover the surface of the water. After the water has been poured in, the aquarium ought to be left for at least a fortnight before the fish are introduced. The water should not be changed, and any which used to replace that lost by evaporation must be introduced in very small quantities, almost day by day. The top of the aquarium ought to be covered with a sheet of glass, resting on a thin layer of cork at each corner, to prevent the inmates from jumping out.

How To Feed The Pish

The food of mature Paradise fish consists of small waterworms (tubifex), shredded raw beef, ants' eggs, and tiny forms of insect life.

If the water has been warmed to the proper temperature of 85° during the summer months, preparations for breeding will be made by the Paradise fish, the male performing by far the greater share of nest-building and care of the eggs and fry.

The nest, formed of air-bubbles and buccal secretion, is often five or six inches across, and is usually at the top of the water, or only an inch or so below. Any eggs which are not laid in the nest are puffed into it by the male. As soon as the female has laid her complement, about 200 or 300 eggs, she should be removed into another vessel previously prepared for her reception, in often happens, she eats her progeny.

The young fish are hatched in about two days, and are tended by the male parent for the next eight or nine, at the end of which time he can be placed with his wife again.

During their quite juvenile days the young can be fed on entomostraca, and subsequently on the food recommended for the adult fishes. The mortality amongst the young is about 75 per cent., but with reasonable care from thirty to forty ought to be reared. The parent fish must never be left in the same vessel as the young, for as soon as the latter have left the nest they will devour them.

Paradise fish are not suitable for keeping in large aquaria with other fish, but must always be kept by themselves, and preferably in pairs.