| In juvenile fish, determining sex is almost | | | | breeding tube. Be aware that this is only |
| impossible. It is only when they begin to | | | | evident during spawning, and should be |
| pair off that an opportunity arises to help | | | | closely observed. |
| in the determination of sex. Juvenile fish, | | | | |
| both male and female, have a rounded dorsal | | | | It has been said that the male discus fish |
| fin, and it is not until they begin to mature | | | | will tend to have a less intense color and |
| that a difference can be detected. As it is | | | | more pattern while the female tends to be |
| never wise to excessively handle the fish, | | | | more colorful but with lesser pattern. I |
| close observation is in order to aid the | | | | disagree, because too many variables are in |
| breeder. | | | | place here, such as the health of the discus, |
| | | | the water parameters, and feeding pattern. |
| In Allnut Enterprises' King Discus Hatchery, | | | | |
| for example, it is an easy process to | | | | In an interesting article by Jeff Richard, he |
| determine who is who, as we have observed | | | | discusses an article from Diskus Brief, a |
| these fish for a while, and can determine the | | | | German publication, which reports a very |
| sex of the pairs we own. This would be true | | | | successful way of determine sex of a discus |
| in any hatchery. But to the uninitiated or | | | | by using simple geometry. Jeff reports, and I |
| casual observer, this would not be easy to | | | | quote: "Picture a discus facing to your |
| do. | | | | left ... you would be looking at its side. |
| | | | Find the Dorsal (Top) and Anal (bottom) fins |
| Some of the identifiers: The male will have | | | | and look where the fins slope down toward the |
| thicker lips to aid him in his fight to | | | | Caudal (tail) fin ... make sure you're |
| protect the female, and will be more | | | | looking at the fins after they have curved |
| aggressive. He will be larger than the | | | | back toward the tail. The Dorsal and Anal |
| female, his forehead is thicker, and we have | | | | Fins become (almost) straight after the fins |
| observed that if the discus are a bit shy, | | | | curve down (or up) toward the Caudal Fin ... |
| the male will have a tendency to stay between | | | | extend an imaginary line along this straight |
| the female and the observer. | | | | section of the 2 fins back toward the tail |
| | | | which just touches the Dorsal & Anal Fins |
| The dorsal fin of the male will be pointed, | | | | past the Caudal Fin. These two imaginary |
| and the female's dorsal fin will be rounded. | | | | lines should intersect behind the fish. The |
| Note that in juvenile discus, this is not | | | | key to sexing the fish is where the lines |
| apparent. | | | | cross the Caudal fin. If they pass through |
| | | | the Caudal Fin, the fish is most likely a |
| The breeding tube of the female, between the | | | | FEMALE. If they miss or just touch the Caudal |
| anus and anal fin, is broader and rounder | | | | Fin, then most likely it is a MALE." |
| than the male, and will have a blunt tip. The | | | | Thanks, Jeff! |
| male, in turn, has a smaller, sharper | | | | |