Article by Bill Ramsden, Photographs by Paul Winters

The following article describes the method that I have adopted over many years and the one that has always proved successful. Other breeders may vary from this method, and can be just as successful - there are no hard and fast rules.

goldfish pond

Summertime - planning for the following Spring

You must start thinking about breeding as early as July or August of the year before you intend to breed. The reason for this is that you must consider what type of fish you want to breed; I would recommend, for the beginner, that a singletail type fish is selected. It is wise not to try and deal with too many varieties at once, so I would suggest that you choose just one or two types and concentrate on them.

July and August is the best time to purchase fish, as this is the time when the breeders are selling their surplus stock. One can buy six or more young fish at a reasonable price and grow these on for the future. This also gives you a good chance of getting both sexes from the same strain. The minimum number of adult fish of one strain that I would recommend at this time would be two females and three males, because it is very easy to lose one or two fish (for numerous reasons, e.g. a long hard winter or when applying heat after the winter when the fish have less resistance to disease). There is very little chance of replacing fish in February or March.

Over-wintering of fish

The next stage is to feed the fish up, so that they have enough body mass to see them through the winter and leave them strong enough to prepare for spawning in the early Spring.

For those who keep their fish outside or in a fish house, you will notice that at the end of October and into November your fish are beginning to slow down and do not require the same amount of food. This is the time to 'clean' your fish and separate the males and the females.

The solution that I use to clean the fish is one measure of terramycin, 80 drops of Formaldehyde and 6 drops of copper sulphate in 4 gallons of water at the right temperature and not forgetting the aeration. After the fish have been in this solution for 20 minutes they are transferred into another container of clean water. In the meantime, your tanks must be given a thorough cleansing with bleach or Milton sterilizing fluid, but be sure that they are completely rinsed out afterwards. (NOTE: omit cleaning if you do not feel confident about it, or if you keep your fish in very clean conditions throughout the year).

For the next two, or two and a half months, the fish should receive practically no food; perhaps a little live food (e.g. daphnia), if the weather is good, but no dry food. If a lot of live food is not available, you could substitute a high protein flake or pellet food. During this time, keep an eye on the fish: if they appear to be suffering due to severe cold or very long periods of cold weather, a little heat may be applied; this must be done very gradually and no more than is absolutely necessary.

Springtime - preparing for breeding

If you decide, say, that you would like to put your fish together for spawning on the 1st of April, then you must subtract six weeks from this date and that gives you the date upon which you should start to raise the temperature by a couple of degrees. Continue to do so each day until the temperature reaches 65 degrees Fahrenheit (18 degrees Centigrade). During this time the fish will start looking for food: start with small quantities of live food and high protein food, increasing the quantity as the temperature rises. Good aeration is required and any excess food must be removed.

A 3 ft (90 cm) or a 4 ft (120 cm) tank is quite suitable for breeding and this must be prepared at least a week before the fish are put together. If possible, leave the tank empty for a couple of weeks, as this will kill off any disease; otherwise, it must be thoroughly cleaned with bleach, Dettol or Milton fluid. All traces of cleansing fluids must, however, be removed afterwards - keep rinsing until all smells have gone. The tank can now be filled to a depth of six inches, with a new air stone to aerate the water. In the meantime, the spawning medium can be prepared: this can consist of bunches of nylon wool, unravelled nylon pan scrubs, natural plants or nylon wool.


Parents: female left, male right. Spawned 24 March 2002

Selecting the fish

Now comes the big day when the fish can be selected and put together in the breeding tank. First select the female: she should be heavy at the rear and protruding on the left-hand side of the body. Try applying a little pressure near the anal area, the body should be very soft.

Note: to sex goldfish, look for the following physical changes that occur at the start of the breeding season: males develop breeding tubercles (white pimples) on the gill covers and on the leading edge of the pectoral fins (see Finnage); females develop a deeper body as the fill with roe, and have a larger vent (just before the anal fin) than the males.

Next is the turn of the males. It is advantageous to use two males to one female, because this will give you a better fertility. They should be chosen for their chasing ability and a good indication of their condition is the presence of breeding tubercles on their gill plates and pectoral fins. The fish must then be put through the same treatment as when bedding them down for the winter; this is to make sure that they will not pass on any disease or parasites to the fry.

goldfish spawning

Spawning the fish

At all times the water temperature which the fish are being transferred into should be at least 65 degrees Fahrenheit (18 degrees Centigrade). The ideal time to introduce your fish into the breeding tank is in the early evening and then the temperature should be raised gradually until it reaches 70 degrees Fahrenheit (20 degrees Centigrade). Sometimes the fish may start chasing during the first night and spawn the next day, but more often than not spawning takes place a few days later. Fish can be stimulated by putting in fresh water from a hose pipe under pressure; this is best carried out at night-time.

The fish will start to spawn early in the morning, and will generally carry on until midday. Do not be in a hurry to separate them if they stop chasing because they will periodically stop for a rest and then start again. Care must be taken to guard against any fish that eat the eggs - these must be removed as soon as possible.

goldfish eggs

Hatching the eggs

On completion of spawning, transfer the fish to a fresh tank with the water at the same temperature; this can then be lowered gradually. On the second day, you will notice that some of the eggs have a furry appearance; these are the infertile eggs and can be ignored. The fertile eggs have a clear appearance and after the first two days you will notice two little black eyes with a curved black line, which is the body structure.

These eggs are very hard to see, but do not despair. If you can only find a few, there will be many more when they hatch out and are free swimming. At 70 degrees Fahrenheit (20 degrees Centigrade) it will take 4 days for the eggs to hatch out. Many of the fry will lie on the bottom of the tank, some will cling to the sides of the tank and others will hang from the spawning medium. The fry carry a food sack which will support them for two days. After this time they will become free swimming and will start looking for food.

goldfish fry

Feeding the fry

The best food at this stage is brine shrimp. This is cultivated by using a large glass jar (e.g. a toffee jar) with 4 pints of water and 2 large tablespoons full of common salt. Dissolve the salt in the water and add 2 teaspoons of brine shrimp eggs. This must be kept at a temperature of between 75 and 80 degrees Fahrenheit (23 - 25 degrees Centigrade) with strong aeration. It will take between 36 to 40 hours for the brine shrimp eggs to hatch. Next, remove the air stone and leave the jar to stand for 10 minutes; the brine shrimp will settle at the bottom of the jar and can be removed by siphoning through a fine tube and filtering through a fine piece of nylon material.

After the first week, the spawning mops can be removed by turning them slowly upside down and gently shaking to make sure that no fry are still attached.

It is very important to start culling the young fish as soon as possible, giving the good fish more room and not wasting resources on substandard fish.


I trust that this information will be of value to you in your future breeding programme.

W. H. Ramsden

Bill Ramsden is a leading fishkeeper and breeder who has judged at all major shows throughout the Country for many years. He is a founder member of the Northern Goldfish and Pondkeepers Society (1959) and has been President of the Society for the past 30 years. He is also Chairman of the Nationwide Goldfish Standards of Great Britain Committee.

Paul Winters was formerly joint secretary of BAS (2002). The photographs are of his Bristol shubunkins raised in that year. Further photographs from the 2003 season are presented below.

goldfish fry at 3 days goldfish fry at 12 days goldfish fry at 12 days

Fry at 3 days old, early April 2003 (left) and at 12 days old (centre and right)

young goldfish at 12 and 26 days young goldfish at 60 days goldfish at 4 months

Fry at 12 days (left) and 26 days (right)

Young at 60 days

Young at 4 months

1 year old Bristol shubunkins

1 year old Bristol shubunkins

Breeders' Notes

For detailed coverage of topics including obtaining good quality stock, selective breeding for desired characteristics, the relative ease or difficulty of breeding the different varieties, culling, feeding, keeping and housing their breeding stock, see the Breeders' Notes under the following pages:

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