2007-02-05 23:09:28 · 7 answers · asked by v 2 in Pets ➔ Fish
This depends on the fish, many are very difficult.
In live bearers such as platties the male has a short tube called gonopodium in place of the anal fin, while the female has a normal triangular anal fin.
In cichlids some species, males and females are readily distinguishable by color, size or shape. For others it is difficult or even impossible to tell the sexes apart in nonbreeding individuals.
Body shape, fin length, and coloration are a few ways in cichlids.
Sexing goldfish is very difficult before they reach sexual maturity.
One way to tell is by looking at the shape of the vent. Females may have rounder convex vents while males have thinner concave vents. The pectoral fins of males may be rather thick and stiff (compared to those of female goldfish) and with a more pronounced outer ray.
Another way to tell is by male goldfish will developing breeding stars on their gill covers and along the first ray of their pectoral fins when they are ready to breed.
This site has a little more information and some pictures as well:
http://aquarium-answers.blogspot.com/2007/02/sexing-fish.html
A good resource for this question with links to Cichlid Research and more:
http://aquarium-info.blogspot.com/
2007-02-06 03:02:13 · answer #1 · answered by Carl Strohmeyer 5 · 0⤊ 0⤋
Depends on the fish. Some are males are more vibrantly coloured(african cichlids) and/or bigger, some males have a modified fin called a gonopodium (livebearers) and some you cant tell externally.
Maybe ask a new question talking about a particular fish and we will be able to help.
2007-02-06 07:40:30 · answer #2 · answered by friskyparrot 2 · 0⤊ 0⤋
Depends on the fish. Sometimes you can tell by their tail, or the color, or their size. I agree with another person, you should ask another question about the specific fish you are wanting to know the sex.
2007-02-06 10:56:59 · answer #3 · answered by nellie1362 2 · 0⤊ 0⤋
usually you can tell with males cos they are brighter colours than females.swordtails have a long sword on male and no sword on female guppy male has fancy back fin and female is plain.most shops can tell you if you ask for a pair any way.some fish you cant tell and since they wont breed in captivity it doesnt matter anyway
2007-02-06 09:33:56 · answer #4 · answered by Anonymous · 0⤊ 0⤋
sure you can ... you must look at they tail ... male tale is longer than females ;)
2007-02-06 07:17:50 · answer #5 · answered by Rolls 1 · 0⤊ 0⤋
males are more vibrantly colored
2007-02-06 07:11:55 · answer #6 · answered by cging22 5 · 0⤊ 0⤋
Ask him(her). (LOL)
2007-02-06 07:13:48 · answer #7 · answered by Harry 5 · 0⤊ 0⤋