When Can You Tell If Your Fish Is A Female Or Male?

[ranapipiens]

I was reading about the breeding stars when someone (already forgot the name, sorry) found out Jackson was a boy. I was wondering if they have to be a certain age or size before they get the breeding stars and how would you be able to tell your fish was a female and not just a late blooming male, how long do the stars stay on (so I could be sure to see them) then again, my fish is a black moor, they will be pretty obvious, but you know, just in case. As of right now I call Hitomi a boy, but his name is androgenous, so it's alright whatevery he turns out to be, he's pretty small right now, I don't know how big exactly because I have nto measured him, but he's pretty small.

[TetraLover]

I've no idea what sex my two are, but I just default on male for some reason. Doesn't matter how many pictures and diagrams of how to sex a goldfish are out there, I can't tell a single danged similarity between those and my fish.

[ranapipiens]

Lol, I usually default on male too, I have 2 hermit crabs and they are both defaulted males, I have two hatchet fish and they are both default males, my iguana and my goldfish are too, IDK why... well, actually i do, my mother is for some ungodly reason deathly afraid of male animals as pets, some reason EVERY species of animal that can be kept as a pet, she has something against the males of the species, "males are stinky" "males are stupid" "males are aggressive" etc. etc. anyway, so it's like I am male-pet deficient or something, lol, out of all the pets my mother has ever had that I have seen was her male yorkie and her male goat, of mine are all my defaulted males, a male dog, 2 male mice and a male rooster, I am in essence rebelling since I can choose the gender of the default pets as long as I don't actually put in the effort to find out, lol, except I suppose eventually my iguana will tell me what gender he is, since they look quite different when full grown, so we shall see.....

[lynda441]

There are a few ways to sex goldfish. This is best done after the fish has reached sexual maturity, which may occur anywhere from 9 months to 2 years after hatching. The problem with determining the age of a fish is difficult because you have no idea when the fish was hatched if you didn't breed it yourself. Size isn't always an indicator because size can be affected by factors such as size of container the fish was raised in, the quality and type of food fed, how healthy the fish has been, etc.

Sexing is easiest to accomplish during breeding, when males chase and nip at females. Chasing, however, is not the most reliable indication as males will chase other males in the absence of a female and fish will sometime chase and nip sick fish or simply there is sometimes the "bully." The breeding stars which look like small white spots or pimples on their operculum (gill covers) and this should not be confused with the parasite, Ich, which would also be on other areas of the body. The breeding stars will usually also be on the upper front edge of the pectoral fins. To determine whether you have a female, when a female is in her breeding period, her body may become larger, indicating that she is carrying eggs. Additionally, her vent (anal opening), which is located under its? underside between the tail and anal fins, will stick out a bit. A male?s vent does not stick out, but instead goes inward.

As with my Jackson, he has white operculum, so taking a picture of the breeding stars would've been virtually impossible unless you were a really great photographer, which I am not. He just happened to turn in just the right way and right light and I was able to see them. I can't just see them by looking at them at any given moment.

Chrissy Bee took a really good picture of her George's breeding stars:

Edited July 18, 2008 by lynda441

[koko]

On darker colored fish its so easy to see it. I have a fish that is a calico white and its much harder to see it on him.

Most males will show there stars when they reach 2-4 years old...Just like that photo and some times on there head if there and Oranda

[lynda441]

One more thing to add, the fish has to be ready to breed. You may have a male, even of breeding age, but if he isn't ready to breed, you won't see the stars. See, the water has to go through a sort of natural cycle, like the outdoors would. A cool/cold winter followed by a warming in the spring. So, if you keep your aquarium the same temperature all the time, you may never see any signs of breeding.

[koko]

Actually sometimes a fish will get alittle over egar and will show stars early. I had one that did that at 2 and the tank was set at 78F. So sometimes its there gens but yes most of the time they need to be ready to breed

[lynda441]

It just came upon me that goldfish are the only equal opportunity fish. The females insist on being just as beautiful and desireable and worthwhile as the males!

[koko]

So true.....

[PHYLAL]

Firstly, sexing young and juvenile goldfish is virtually impossible without killing and examining the internal organs, you have to wait until the fish reach breeding age, usually one year old, sometimes several years. Secondly, sexing adult goldfish out of the breeding season is difficult, because the sexually distinguishing features only develop during the breeding season (or for aquarists, when you prep them). That said, females are usually deeper in the body than males. .

Body Location

Mature Male

Mature Female

Gill plates

White bumps called tubercles present

Few or no tubercles

Leading ray of pectoral fins (paired front swimming fins behind gills)

White bumps called tubercles present; thicker edge; more pointed fin

Few or no tubercles; thinner edge; more rounded fin

Leading ray of anal fins (small fins near vent)

Thinner

Thicker

Vent (where wastes and eggs or sperm exit the fish)

Concave (goes in); smaller opening

Convex (sticks out); larger opening

Behavior

Chaser

Chased and harassed

Abdomen

Smaller; may have a ridge; more firm abdomen

Larger, fat; no abdomen ridge; more pliable abdomen (if full of eggs)

General body shape

Thinner; longer; symmetrical from above

Fatter; shorter; asymmetrical from above (if full of eggs)

[vickielm]

Well, I donno. Its like I just said in another thread...Florence has breeding stars, so she is a he. But I'm not changing his name, so it doesn't really matter to me.

[lynda441]

Well, I donno. Its like I just said in another thread...Florence has breeding stars, so she is a he. But I'm not changing his name, so it doesn't really matter to me.

Nope, it doesn't matter, but it is kinda just fun to know... and it was especially exciting for me to see breeding stars for the very first time!