The neon tetra is usually regarded as the most beautiful of all aquarium fish, and rightly deserves this honour. Even colour photography can’t capture the neon-like fluorescence given off by a vivid streak of bluish green running from the eye to the tail, with a dark olive green border on the top and below. A nicely planted aquarium with about twenty of this species is an unforgettable sight.
It also has a red marking which has the peculiarity of staining white paper when a dead specimen is laid upon it; this indicates that the colouring matter is a pigment, and accounts for its sustained brilliance when the fish is frightened or excited.
Regrettably, very small is recognized about the neon tetras breeding habits. They’ve been bred successfully in the aquarium, but not consistently, for the eggs tend to disappear in the water. W. T. Innes gives the following process in his Exotic Aquarium Fishes.
As females show signs of filling with roe they’re separated from the males, and when regarded as ripe a single pair is placed at night in a bare tank containing newly drawn water that has stood not over one day. As spawn is dropped on the bottom of the tank, the female tries to eat it, but the male drives her away. Eggs are lifted by dip tube and hatched in an additional container, bare except for a large flat stone raised about an inch. The newly hatched young, which are little and challenging to see, attach themselves by their noses to the underside of the stone. They’re reared by the standard infusoria, brine shrimp, sifted daphnia schedule.
Effective spawning have been induced in America by the following process. Water with a pH value of 6.5 – 7 is utilized, and this pH should be checked once a week and corrected if essential by the addition of sodium phosphate. This correction should, needless to say, be done gradually over a period of 3 to four days.
The water should also be very soft, approximately 50 parts/million, and made up of distilled water and tap water. It is an benefit to maintain neons in this soft water even prior to breeding, and, if feasible, really raise them in it. Newly acquired specimens, even if not reared in it, should be transferred to soft water upon arrival.
Cleanliness is of fantastic significance. The eggs are occasionally destroyed by bacteria which penetrate the protective membrane. Every precaution feasible should be taken to make certain everything is spotless that enters the tank; nets, thermometer, plants, cover glass, etc., should be as near sterile as they could be made. This reduces the possibility of bacteria entering and maybe destroying the eggs of an otherwise effective spawning. A little tank, about 3 gallons capacity, has an benefit over larger ones. This should be planted with a bunch of fine-leafed plants that have initial been sterilised by putting them in water containing one tablespoonful of powdered alum per two quarts for ten minutes.
Introduce the fish into the tank during the evening, initial sterilising them by putting them into a separate tank of water to which one teaspoonful of sea salt per gallon and sufficient permanganate of potash to turn the water pink has been added. Leave them in this answer for ten minutes. It is essential to make certain that this answer is at the exact same temperature, pH, and softness as the breeding tank.
The fish, if in breeding condition, should begin to spawn the next morning. If they don’t spawn during that day, remove about one half of the water and replace with fresh distilled water, slightly cooler. After a effective spawning, the tank should be blacked out for a period of five days.
The eggs hatch in approximately 24 hours and vary between 15 to 100. Remove the parents instantly after spawning, and return them to their own tank via the sterilising tank. Whilst the adult fish are in the breeding tank, they could be fed on half-grown brine shrimps. Still keeping in mind the necessity for cleanliness, rinse them for ten minutes in a answer of water and rock salt, two tablespoons of salt to two ounces of water. Finally, rinse them in clean tap water prior to transferring them into the breeding tank.
Begin feeding the fry on the fifth day. It is fatal to feed them on infusoria. Use instead hard-boiled egg yolk squeezed via a piece of fine muslin and mixed with distilled water. This mix should be sterilised by boiling for ten minutes in a stoppered bottle. The stopper should have a little hole in it to stop it exploding. Feed twice every day approximately one drop for every ten fry.
Warning – make certain the egg infusion is always fresh, it’ll maintain in a refrigerator up to a week. Fry grain should be fed on the eighth day. This food is light and will float on the surface where the fry are now swimming.
After two weeks the fry could be fed newly hatched brine shrimps. At the exact same time, the tank should be gradually lightened by removing a portion of the covering. The complete lightening of the tank should be over a period of about a week.