More on breeding I

A temperature that is excessively high forces the growth of the fish and seriously weakens their constitution. It sometimes overdevelops the finnage too.

All along the line, inferior fish should be removed. For example, with fantails, veiltails and Moors; the ones with only single tails instead of the prized forked tails can be detected well before they are fourteen days old and should be taken out. Later as body shapes develop, the poor quality should be ruthlessly sacrificed. By the time three months have passed, the selection should have been completed.

Within two weeks, the fry are past the infusoria stage and will swallow finely powdered dry foods, dried eggs, oatmeal, etc. Nevertheless, take great care not to foul the water. It should be partly changed especially if snails are not able to cope with the work. After a few more days, micro worms, finely sifted Daphnia and not quite such powdered dry food should be introduced to the fish. Within three to four weeks, the last stage of tubifex and chopped white worms can be fed. By this time, the worst danger is over.

In the meantime, the difficulty is now to get the fish to colour. The scales should be transparent so that a good body colour can be seen through them. Opaque coloured scales would result in a dark, uninteresting fish. However if the parents are from good stock, the required temperature maintained, space is ample, plenty of live foods were constantly given and enough sunlight, the fry should colour within eight months. Some will colour within four months. A constant drip flow of water into the aquarium helps enormously. If a year goes by without the colour showing through, then having a good fish is doubtful. The general conditions, including the surrounding colours and their inter-action with sunlight influence the fry development.

The above descriptions apply to coldwater aquarium fish in general.

More on breeding

We are still talking on breeding of coldwater fish.

The eggs, transparent, adhesive and the size of a pin head are laid in clusters, no two individual eggs being in contact. Within twenty four to forty eight hours, the infertile ones turn opaque, almost milky. There always seem so many of these that we might be frustrated, but patience and diligence are usually rewarded.

70 to 75 degrees F is a good temperature for the incubation and in four days, fry should appear. They are free swimming within forty eight hours and will need green water and infusoria. Most of all they need plenty of space. Warmth, space and ample food are all essential.

As many as one thousand fry can result from a good spawning, so that the problem of space is pressing. It is strongly advised to pick out the best specimens as soon as is practicable and to concentrate on them alone, disposing of the others. Aeration is helpful right from the commencement of the incubation period.

Breeding of coldwater fish III

Sexing the fish is difficult. In exotic specimens such as the Veil-tail and the Fantail, the males are often as full bodied as the females. Only at breeding condition do the male tubercles appear as raised white dots on the gill plates and on the pectoral fins. Absence of these dots might mean that the fish is a female or that it is a male not ready to breed.

Once spawning starts, however, the females can easily be picked out as they are vigorously chased and nuzzled by the males. Two or more males should be used to 'drive' each female in the well-known chase which may last a few hours or even two or three days. Thus frequent replacements of plants to catch the eggs as they are scattered and plenty of swimming room are essential.

In the aquarium, a good supply of aeration helps. The water temperature should not be below 60 degrees F or above 80 degrees F. In the earlier temperature the fish tend to be sluggish and in the other, the fish will lack oxygen. Temperature between 68 - 72 degrees F is ideal while bright light, especially sunlight is appreciated.

Breeding of coldwater fish II

As mentioned earlier, ponds should be periodically emptied to ensure that overlooked eggs or fry from previous matings have not remained behind to grow and to interbreed with the chosen parents.

If we decides to do the breeding in ponds, we may still be well advised to hatch the eggs in an aquarium and to keep the fry indoors for the first crucial ten weeks. A pond that is more or less bare, except for ideal spawning plants at the shallow edge, practically forces the fish to spawn on these plants which can then easily be removed to an aquarium. Thus, fresh supplies of plants should be available to keep up with the spawning.

It is important that these bunches of plants be frequently rinsed to shake off dead algae or any other such foreign matter that could later prevent the eggs adhering properly.

If the parents are not separated from the eggs, many of these will be eaten. Even more important, once the fry have appeared it is the slower swimming ones that get less of the food and are more subject to being attacked. The slower swimmers are usually those with the longer finnage - the very fish that we would most like to save.

Obviously, spawning starts with good-quality parents that have been separately brought up to the best possible condition. It is a bad mistake to use inferior fish as the resulting fry are just not worth the trouble. Each prospective parent should be known to have come from good stock and even if not perfect in itself, be known to be capable of producing good young.

Breeding of coldwater fish I

The first question when deciding to breed coldwater fish is, should we breed in a pond or in an aquarium.

Two advantages of the pond are:

Large volume of water

In good weather, natural foods for the young fish are abundance

Breeding in ponds has its disadvantages too:

Especially in British climate, apart from extremes of heat or frost and ice, the normal temperature variations are very great and there is little that we can do to control them. Furthermore, these changes are rapid, occurring within a few hours.

There is also a great discrepancy in the amount of light, especially sunlight and an evenly spread supply is almost hopeless.

The above two disadvantages however have their attenuating factors. Although the atmospheric temperature changes very quickly, a fairly large volume of water is affected only slowly and cushions the fish from the worst of the shock. This is if the water is 3 - 4 feet deep. Secondly, the fish seem to have a natural ability to pick out the coming weather and will normally spawn just at the start of a good spell. Nevertheless the good weather, especially in Britain have a nasty tendency to fade off after a very few days.

Though natural foods are abundant in open ponds, so too on occasions are fish lice and water enemies. The pond should thus be capable of being thoroughly cleaned.

Breeding tips

If the water in the shallow breeding tank is too low to hold an immersion thermostat comfortably, the latter can be immersed into a jar standing in the tank. Thus the water temperature of the tank will govern that of the water in the jar, so ensuring correct response by the thermostat.

In removing fry, it is advisable to use a fry catcher, as netting may harm them. This is used in a scooping action. The fry are being allowed to swim into the bowl.

Keep the water level of the rearing tank well below that of the tank sides as a protection against draughts. A glass cover is an additional protection against temperature fluctuations and dust. This is important at this fry stage.

Breeding is all about conditions, waters, fish, foods, sunlight and the likes which vary from place to place, time to time. Patience is therefore essential, as periodical failures and disappointments are quite certain to occur.

Infertile eggs

Eggs that prove infertile, often becoming covered with fungus should be removed. However, effort should be made to find out why they do not hatch in the normal way. It is often found that some, or even many, eggs are covered with fungus but it is rare for all to be bad.

Snails eat eggs and should be removed from the breeding tank. But in rearing tank, snails help to keep the bottom clean. They too do not eat the fry.

Why eggs are infertile?

Wrong temperature

Too much or too little light

Dirt

Infected infusoria culture that breeds fish enemies or harmful bacteria

Unsuitable water that might contain harmful gases. We can either filter or use rainwater to avoid this problem.

Water PH. If new water has been used, try ‘seasoned’ water. Leave tap water in bright light for a day; without disturbing the precipitate that will have formed at the bottom, siphon off the water in to another clean container and leave it there again in the sunlight to mature for a further twenty four hours or forty eight hours. The siphoning gets rid of any insoluble or floating matter.

Eggs not fertilized: due to the pair of adults do not harmonize. We can use two or three males to one female.

The tank is too small.

How to move the eggs

When lifting out the plants holding the eggs, sudden temperature changes should be avoided. Moreover, do not expose them to the air too. So, how should we do this? Just place a bowl under these plants, raise the bowl, taking care to keep the plants, roots if any, and eggs submerged and so to move them still in their same water to the rearing tank of the same temperature.

General questions such as whether the water should be ‘old’, green or what its PH should be, or whether the floor should be spotlessly clean or covered with some mulm, can only be answered in the case of particular breeding adult fish. Nonetheless, the fry will need ‘mature’ water for their growth.

The same applies to temperature and aeration. What we should bear in mind is that fish accustomed to constant aeration will have to be taught gradually to do without it before they are transferred to still waters. If the tank is large enough, there should be no need for aeration.

In breeding, cleanliness is the utmost important thing. Danger of infection will have to be watched most carefully.

Types of eggs

Different types of fish have varying preferences and methods of laying their eggs but the following general remarks will serve as guideline:

Adhesive eggs
Fish are being careful when choosing the spot where these adhesive eggs will be laid. They usually choose broad leaves of a strongly-growing plant. Fish lay eggs at the underside or inside of small flower pots or even on the hollow of a conveniently shaped rock. Some fish however merely scatter their adhesive eggs which should be caught by bushy plants group in bunches.

Non adhesive eggs
This type of eggs are either scattered on thickets of plants, noticeably on those with fine leaves. The plant not only serves to catch the eggs but hiding them and the newly hatched fry from the dangers of being eaten. Alternatively, the eggs are placed in carefully formed and guarded nest. Some fish use a hollow in the sand while some fish are bubble nest builders.

Feeding the fish with infusoria

The best way is by ‘drip method’. How should we do this? Just fix a jar containing the infusoria water above the tank level and the water is allowed to drip into the tank through the rubber tube. The rate of flow can be regulated by a type of clip that can be adjusted to squeeze the rubber tube at any given pressure. Therefore the bigger the opening left inside the tube the greater the flow of infusoria.

How much should we feed the infusoria to the baby fish? The only advice is to use common sense but infusoria must be given early and constantly until the fry have outgrown the need for it. The bellies of the fry should always be full. Continue feeding the fry until they are about three times their original size. If we stop feeding too early, the fry may die. Feeding them with infusoria too long may stop their growth.

The real problem is when the fry are too big for infusoria and too small for ordinary foods. Rotifers, newly-hatched brine shrimps and dry powdered food can be fed to the fry during this difficult stage. Later, finely sifted daphnia can be introduced to the fry. Nevertheless, if the fry spit out the food, it is still too big for them. Use a magnifying glass to check on this.

In addition, at this stage, fry should be fed frequently; up to eight times per day. A limited amount of sediment should be allowed to accumulate as it helps to grow the plants and infusoria.

The above is a general guide on how to feed fry with infusoria. What we must bear in mind is certain type of fish (fry) needs more detail guides.

Preparing infusoria

Infusoria can be prepared in many ways, some of which as follows:

Method 1:
Leave outside leaves of a lettuce in water and in bright light for three or four days. When the water especially round the leaves becomes white or milky, the culture is ready. One drop examined under a microscope will be seen to be teeming with life, appearing as continuously moving dust-like particles. Pond water (free of all enemies) is better than tap water. After about four days, the culture “dies”.

About three bruised leaves per quart of water can be used in this method. Bruising hastens the decomposition of the leaves and the birth of infusoria.

Method 2:
Leave finely sliced potatoes or any other vegetable in water till they begin to smell. Cow dung gives especially small infusoria that can be used for tiny fish.

Method 3:
Pour boiling water on chopped up hay, leaving it to stand in the sunlight till the water becomes light brown.

Method 4:
Using some such mixture as the peel of one potato, one split pea, one yellow skin of a banana, one spinach leaf, thirty drops of milk, one tiny piece of fish to about two gallons of water and leave in the light as described above.

All the above four cultures smell and go foul after three to five days.

Method 5
To overcome this difficulty the cultures can be sterilized. Slow boil for twenty minutes a mixture of almost any vegetable. This slow boil will kill the bacteria of putrefaction. Then the mixture should be left to cool for a day and be carefully protected against dust. We may call this ‘the culture’.

At the same time, similarly boil for twenty minutes separate quarts of water, each containing one of the above ingredients (hay, lettuce, potato, etc). Pour into separate jars and leave to cool for a day, protected from the dust.

Next add six or seven drops of the culture to each jar, keep protected from dust and leave in the bright light for three days. The water will be teeming with life and the infusoria is ready for use.

Advantages of method 5:

The different infusoria of oatmeal, hay, lettuce, etc are separate and fish will soon show which particular one they prefer

The preparation will not ‘die’ under two weeks

There is practically no smell.

Risk of infection is greatly reduced if all implements are sterilized.

All the five methods of making infusoria, are affected by temperature. If the infusoria water is at 80 degrees F or above, the cycle of events is accelerated that makes the culture ready sooner but it dies more quickly. Whereas under 60 degrees F, the development is slow. The best temperature is therefore between 65 to 68 degrees F. Infusoria, like fish, however is affected by temperature changes. Therefore they will tend to suffer if put in an aquarium with vast different in water temperature.

Rearing and feeding the fry

The mating and spawning process is often easier than the rearing of the fry. The commonest difficulties are insufficient or unsuitable food at the early stages and lack of space.

When the eggs are hatched, or the viviparous babies are born, in both instances a ‘yolk sac’ is attached to the fry. It supplies sufficient food for the initial period which may last from a few hours to three days, especially if supplemented by liberal quantities of green water to the tank. Green water is rich in baby-food!

When the yolk-sac is gone, it is our responsibility to feed the fry. This is done by providing infusoria early and constantly.

What is infusoria? Infusoria are living organisms in water on which fish can live until they have grown enough to eat normal foods.

Before we discuss more on infusoria, let’s talk about the importance of breeding trap. Breeding trap is used inside the rearing tank, so as to separate the parents from the eggs or the young. These traps can be done by using finely meshed wire, or any method allowing the eggs or live babies to drop through gaps into the rearing tank. The gaps must be just big enough for them but too small to allow the adult fish to follow. This is necessary if the parents are likely to eat the young fish or their eggs. Otherwise, it is not necessary.

Choosing and conditiong the parents

It is important to choose the parents when we intend to breed. Size, shape, colour, finnage and so on should be considered. Moreover, both should like each other! The best way to ensure this is to place a group of adult fish in a tank and wait for them to pair off. The chosen ones then are being transferred to separate tanks.

With the egg-layers, two or even more males are often used with one female. It is usual to put the weaker fish (often the female) in the mating tank first, so that it is already feeling at home before meeting the other fish.

Fish will often spawn the next morning if they are placed in the mating tank at night. Better still, if they can be put together at dawn, they will tend to spawn almost at once.

Green water and/or two hours daily of sunlight are helpful in bringing the parents to breeding condition. Live foods are necessary too. Feed them with daphnia, tubifex worms, chopped earthworms etc, twice a day. Each feeding is to last about 15 – 30 minutes. However, too many white worms will tend to make the fish fat and reluctant to spawn. The rule is to feed well but not too heavily.

On the other hand, it must be remembered that feeding frequency depends on the temperature of water too as it affects the eating habit of the fish, both of tropical and coldwater.

In mating tank, the water temperature is often raised when the adult fish are introduced. This higher temperature can be maintained till the eggs are hatched and even for the early stages of the fry. Nonetheless the high temperature should not be prolonged as it will weaken the fry.

Once spawning is completed, the parents are separated from the eggs or young, except for a few types of fish where males are left with the nest for about a week.

Breeding and rearing tropical fish

Ever thought of breeding your fish?

Some fish give birth direct to fully-formed live baby fish. These are called viviparous. From them, many interesting cross-breeds, or hybrids have been evolved.

Others lay eggs first in the normal way; which can be adhesive or not and can be scattered or carefully guarded. The nests vary; including floating air bubbles with the eggs individually wrapped in these hygienic containers.

In breeding, the problems are not in the mating and spawning but in rearing the fry. This is one of the main reasons it is so much easier to breed the viviparous kinds as the eggs are fertilized and hatched inside the mother’s body. Thus it passes the danger stage when born.

Breeding problems differ between fish. There is no particular season for the breeding of tropicals because it is nearly always possible to provide ideal conditions, the supply of live foods and sunlight.

The first thing to consider when we intend to breed is the breeding tank itself. The breeding tank is often shallow; perhaps 15 cm – 22 cm deep. It however should not be too small, not less than 35 cm long by 20 cm high and 25 cm wide as many fish get nervous and excited when confined in a small space.

A large breeding tank is not necessary although it is essential for the successful rearing of the young. Overcrowding can retard the growth and strength of fish, cause illness and destroy the weaker fish. For rearing too, a deeper tank, around 30 cm is advantageous since it encourages the development of better specimens.

When plants are being used, the planted side of the breeding tank should always be towards the light. This will enable the fry to have hiding places.