How to identify the sex of the goldfish?

[SniperY]

Can you tell whether you have a male or a female goldfish? It is a difficult task at best but there are a few ways to help determine the sex of your fish. It is a most difficult task on fry less than a year old, but as a general rule, females are likely to be bigger than the males of the same age. *When they reach spawning age, and the eggs begin to mature in the female fish, she will thicken in the ventral area. *At the same time, the male will start to develop small white tubercles on his gill plates and on the leading rays of his fins, particularly on the first ray of the pectoral fin which can usually be detected on fish with head growth.

Then there is the anal opening. *With practice, so I'm told you can distinguish the difference between the sexes. *Below are pictures of the anal opening of the male and female goldfish. *These differences become much more apparent as spawning time approaches.

A & B are the female anal openings. *They are larger, protrude slightly and is round in shape. *The anal fin is thicker and has a heavier first anal fin spine.


The male is C & D. *The male's opening is small and oval with no noticeable anal fin thickness.


These differences become more apparent as spawning time approaches. *The female opening will be larger and more distended when the eggs are ripe. *When the male is ready, milt may be pushed out of the ventral opening by running a finger lightly along the sides of the fish, which shouldn't be necessary as the tubercles will be plainly viewed. *

[SniperY]

Firstly, sexing young and juvenile goldfish is virtually impossible, you have to wait until the fish reach breeding age (usually one year old).

Secondly, sexing adult goldfish out of the breeding season is difficult, because the sexually distinguishing features only develop during the breeding season (in the spring time). That said, females may be deeper in the body than males.

Physical sexual characters

During the breeding season, the following physical features develop:

* males develop breeding tubercles (white pimples) on the gill covers and on the leading edge of the pectoral fins
* females develop a deeper body as they fill with roe (eggs), and have a larger vent (just before the anal fin) than the males

Behavioural sexual characters

Put quite simply - in the breeding season, males chase after females to induce them to spawn. Easy? No. Why? Because males will chase each other in the absence of females. Use the physical features as well as the chasing behaviour to tell the sexes apart!

Male breeding tubercles
Illustrated above are the small white breeding tubercles that develop on the gill covers and the leading edges of the pectoral fins of males. It has been suggested that these may play a role in stimulating the female to spawn during chasing.

[SniperY]

Vents

The female vent enlarges slightly and appears slightly out-turned (convex), as shown above.

[SniperY]

The male vent remains normal (slightly concave) in appearance, as shown above. (The vent is the common/single orifice for reproduction and excretion).

[Anf]

My method last time I use when I'm breeding GF
is 2 press n see wat come out(Egg or Milt) den cfm the sexes. :stick_out_tongue: :hmmm: :confused_1:

[Flipper]

Hi guys, please kindly refrain from posting unnecessary comment in the sticky thread. Thanks

[LIMT26]

all this info must be for wat age of the fishes in order to apply correctly ?
I dun know, maybe think that when fishes too small cant really see the slightly concave loh so maybe when big then po out and become female ?


The male vent remains normal (slightly concave) in appearance, as shown above. (The vent is the common/single orifice for reproduction and excretion).