This page contains short articles about the history of goldfish and colour and finnage in goldfish, how to keep them (Golden Rules), common diseases, and how to breed them; at the bottom of the page there is a glossary of terms. Follow the links on the left to access these topics.
Goldfish are the domesticated Asiatic subspecies of Carassius auratus, the gibel carp, a species that naturally shows a wide range of morphological variation when raised in different environments. In its native China it inhabits rivers, streams, ponds, lakes and ditches, living in running, still and even stagnant water from 10°C to 32°C, growing to about 30 cm in length and 2.5 kg in weight within 2-3 years and living for about 10 years. It is a delicious food fish! It crosses readily with any ornamental goldfish, producing viable offspring. To the right is a picture of the Asiatic gibel carp (picture courtesy of Man Shek-Hay (1982) Hong Kong Goldfish, Urban Council, Hong Kong, taken by the author at Plover Cove Reservoir, Hong Kong - the fish was safely returned to the water).
All morphological changes from the wild type are the result of genetic mutations which man has spotted and favoured by selective line breeding to perpetuate them according to his fancy, although there is a strong tendency to revert to wild type. Human husbandry of this species has unlocked its huge genetic potential, but it has taken a tremendous amount of effort to select and stabilize desirable gene combinations, as can be appreciated from the 1700-year chronology given below:
|Chun d. (265-419)||gold colouration first recorded (d. = dynasty)|
|Tang d. (618-907)||goldfish raised in captivity (in ponds) in Buddhist monasteries; common goldfish probably established|
|Nan Song d. (1127-1279)||goldfish raised in domestic ponds; white and red-and-white colouration developed|
|Ming d. (1368-1644)||goldfish raised in bowls indoors as pets, enabling selection for mutations that would not have survived (or been observed) in ponds; double tail and anal fins, dorsal-less condition and short body evolved, eggfish developed|
|1596||matt scales and calico colouration; keeping of fancy goldfish, once the preserve of the aristocracy, now widespread.|
|1603||goldfish first exported to Japan|
|1611||goldfish first exported to Europe (Portugal)|
|Ching d. (1644-1911)||bronze and blue colouration|
|1728||goldfish first bred in Europe (Holland)|
|1758||goldfish classified as Cyprinus auratus by Linnaeus (reclassified as Carassius auratus in 1949)|
|1874||goldfish first exported to America|
|1900||pompon and pearlscale; shubunkin colouration developed in Japan|
|early 1900s||comet and veiltail|
|1934||Bristol shubunkin standard promulgated|
(In that ancient records could have been made then lost, or could considerably post-date the events they describe, one should be circumspect about such chronologies).
Most of the changes are recessive compared with the wild type (hence the tendency to revert to wild type) but are dominant amongst domesticated stock (such as the mutation for matt scales). Where alleles (versions of a gene, one inherited from each parent) are both dominant (co-dominant), an intermediate condition between the two results; for example, nacreous scales (see Colour below) occur when the genes for both reflective and matt scales are present.
The only character inherited in a simple Mendelian manner is the globe eye condition; all the other characters are polygenic.
From silks to ceramics to jade carvings, goldfish have found their way into Chinese art since the Ming dynasty, when they began to be kept as pets. The usual aspect was the top view until glass tanks were introduced, when side views began to feature. Illustrated on the right is a modern Chinese jade carving of fancy goldfish types, of exceptional quality; click on the image for an enlargement and a second, equally fine example, plus a few words of comment.
Several normally drab species have a natural tendency to produce red-golden colouration, including the orfe and the tench, the golden forms of which are familiar to fishkeepers; the goldfish (the golden form of the gibel carp) was first recorded in the Chun dynasty (265-419 A.D.). Some 800 years later, red and white colouration was first recorded. After a further 300 years calico fish were first recorded, but these were lacking in blue, which first appeared some 100-200 years later during the Ching dynasty (1644-1911 AD) together with bronze. Finally, shubunkins first appeared in Japan about 100 years ago, and the Bristol shubunkin standard was drawn up in 1934.
The colour of goldfish is environmentally influenced, light being the most important factor: fish raised in a dim environment (such as deeper ponds, rivers, etc) develop (and retain) pale colouration, whereas fish raised in a bright environment develop brighter, saturated colours. Diet also affects colour, and a number of colour-enhancing goldfish foods are available, although the effectiveness of these varies.
There are three types of pigment cells in goldfish (according to the latest research from Aquarian in 2006):
|black||melanophores containing the dark pigment melanin|
|red||erythrophores containing two classes of pigment, carotenids and pteridines; animals including fish cannot themselves synthesize carotenids and need to acquire them in their diet|
|yellow||xanthophores containing carotenid pigments|
Most pigments are located in chromatophore cells, but pigments may also be found 'free' on the body surface or deeper within the body tissues. The presence or absence of pigment cells in different combinations, together with variations in the chemical composition of the pigments and the location of the pigments, gives the following range of colours:
|wild||in wild goldfish, melanophores and xanthophores are abundant, together with a well-developed guanine (silvery) layer in the skin (see next section below); this combination of pigments gives the brown upper body surface (adaptive for camouflage when viewed from above) and the silvery-grey flanks (adaptive for camouflage when seen from the sides and below)|
|gold||when melanophores are absent (as a result of genetic mutation), the fish is gold, orange or yellow, depending upon the position and number of erythrophores and xanthophores present|
|red||goldfish with red colouration have abundant erythrophores present|
|white||white goldfish have no pigment cells|
|bronze||melanophores mixed with xanthophores all over the body surface (as distinct from the wild-type pigment distribution) give different hues of bronze and iron, including chocolate brown|
|blue||in nacreous/matt fish (see below), when there are very few melanophores and these are located deep within the skin (in areas where there are no overlying xanthophores or erythrophores), the apparent colour to the observer is blue|
|black||black goldfish have abundant melanophores lying close to the skin, giving a matt, velvety black if guanine is absent and a metallic black if guanine is present; metallic fish with less abundant melanophores are grey, although this is often marketed as 'blue'|
In addition to pigment cells, there is a guanine layer in the skin just below the scales. There are two classes of cells containing guanine:
|leucophores||these contain small crystals of guanine|
|iridophores||these contain large crystals of guanine and produce the iridescence and reflectivity of the body surface|
All goldfish scales are in fact transparent; the nature of the guanine layer beneath the scales gives the following range of effects:
|guanine present||silvery, reflective scales|
|nacreous (dull mother-of-pearl) scales|
|guanine absent||matt scales|
All ornamental goldfish are born with one of three colour types: wild type, bronze or pink (albino). The pinks and bronzes are culled by selective breeders, and the wild type colouration slowly changes (as melanophores are gradually lost) from black/grey to the adult, ornamental colouration.
There are two ornamental colour groups in goldfish:
Metallic fish may be either all the same colour (self-coloured), the range of colours being red, orange, yellow, 'blue', brown and black, or a mix of colours (variegated), the colours being as before with the addition of silver and arranged in a pleasing pattern similar on each side. Metallic fish have reflective scales owing to the guanine layer present in the skin (see above); pigment cells are on the surface of the skin and colours appear as burnished metal on the body and should be spread throughout the fish including the fins.
Many metallic and variegated fish have dull body colour and lack colour in all but the roots of the fins; fully coloured fish are the more highly prized and do better in shows.
Calico fish have a varying pattern of a few fully reflective scales (guanine present) and mostly matt scales (guanine absent) and nacreous scales (guanine partly present). Where matt scales are present, the following effects are seen: if there are no pigment cells then the body appears pink; if pigment cells are present at depth within the skin then melanophores appear to give a background blue colour (rather than black) and other colours appear more subtle including violet, grey and brown; if pigment cells are present on the surface then matt (rather than reflective) colours are seen.
When breeding calico fish, generally only 50% of fry are calico, 25% are pinks and 25% are bronzes.
A balance of colours and reflective properties with an overall blue background is regarded as the ideal calico combination, and has a special term: shubunkin (which means red brocade in Japanese, the name coming from the overall red-on-blue colour pattern).
The term seems to be used for singletail fish only, namely the London and Bristol shubunkins and the Japanese shubunkin (the 'comet' shubunkin).
All individual fins in goldfish are made up of a double layer; these lie flush against each other, giving a single fin two layers thick. The common goldfish, comet, London and Bristol shubunkins are all single-finned like the wild type ancestor.
If the fin layers split apart and grow separately from each other a double fin results, each only one layer thick. The double caudal and anal fins of the twintail varieties appeared as mutations in the Ming dynasty (some 600 years ago), as did the absence of a dorsal fin; these three characters, together with the shorter, deeper body shape, go to make up the eggfish, which is the oldest of the short-bodied twintail types and is the basis of the lionhead, pompon, celestial and bubble eye types.
There are long-bodied twintail types with the caudal fin completely divided, for example the jikin (or peacock tail) and the wakin, and long-bodied tri-tail types in which only the lower lobe is divided; these are less familiar to us in the West than the short-bodied twintails.
Then there are the short-bodied, long-finned twintails, which were developed from a short-finned twintail precursor (similar to the eggfish but with a dorsal fin): veiltails, orandas, globe eyes and the broadtail moor.
The paired (pectoral and pelvic) fins prevent the fish from pitching (rocking up and down lengthwise) in the water; the median (caudal, dorsal and anal) fins prevent it from yawing (wandering) and rolling (rocking from side to side); forward movement is achieved by S-shaped undulations of the body and caudal fin; steering and precise control of movement are achieved by varying the angle of the pectoral fins.
The show standards used by BAS and illustrated in this website are the Nationwide Goldfish Standards of Great Britain published in 1995, jointly produced by four societies:
Four new standards are under development for the jikin, wakin, tosakin and ranchu; these are nearly complete and should be published in early 2010.
All of the approved varieties are judged on a common basis at shows. The maximum points that may be awarded are as follows:
|condition and deportment||20|
|Anal fin||The lower fin just before the tail|
|Anterior||Towards the front of the fish|
|Body||A fish excluding the fins|
|Brown||Also described as chocolate|
|Calico||Mixture of colours and reflective qualities|
|Caudal fin||The tail|
|Condition||The apparent state of health|
|Cranial||Top of the head|
|Deportment||The way in which a fish carries itself|
|Dorsal||Of the upper surface|
|Dorsal fin||The single fin on top of the back|
|Finnage||The fin complement of a fish|
|Hood||Rasberry-like growth on the head|
|Infra-orbital||Below the eyes|
|Matt||Without a shiny appearance|
|Metallic||With the appearance of being shining metal|
|Mottled||Marked with patches of various colours|
|Nacreous||With a dull mother-of-pearl shine|
|Opercular||Over the gill plates|
|Pectoral fins||The first, forward pair of fins|
|Peduncle||Where the tail joins the body|
|Pelvic fins||The second, ventral pair of fins|
|Posterior||Towards the rear of the fish|
|Self-coloured||Having only a single colour, eg red|
|Standard||The ideal fish|
|Trailing edge||Posterior edge of caudal fin|
|Ventral||Of the lower surface|
© Bristol Aquarists' Society