Sexing baby/young guppies?

T

trailmule

Large Fish
#1
Jan 2, 2008
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#1
I just got 4 small guppies to replace the neons in my 10 gal. How do you tell if they are male or female when they are small? The ones I have are about 3/4" long.... I have not been able to find a decent website with pictures to compare them to, so if anyone has one, please let me know.

If anyone has experience breeding them and can tell me how to sex them I would appreciate it. I can tell them difference when they are bigger.....

Thanks

-TM
 

ishar

ishar

MFT Staff
#3
Jul 27, 2007
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Hamilton, ON.
#3
well there a few ways, but only one surefire way.

One way to tell is that as they mature the males' tails will become much more colourful and vibrant than the females'. However I am sure some strains out there are different and wouldn't show up quite the same way as this, so it is sort of a case by case sexing.

However the surefire way to do it is once they really begin maturing the males will grow a gonopodium. It is the male's reproductive organ and it develops from the normal anal fin into a long and slender 'fin' that can actually move (they can point with it sideways and forwards and stuff). It usually takes around a month for this to occur so be patient. Once it develops you will know it for sure. However if none develop in the next few weeks then they are likely all females.

Hope that helps :).
 

T

trailmule

Large Fish
#4
Jan 2, 2008
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#4
Well... These are not fancy guppies per se... I convinced one of the guys at my lfs to give me 4 feeder guppies I liked. (they have a "no choice of feeder fish" sign) They are a silverish color with patches of iridesent (sp?) reds/greens/blues/blacks. Kinda patchwork I guess. Certainly not the dull brownish guppy one thinks of with the word "feeder guppy"

Anyways, it appears as though they are all male, as I can see what looks like the long anal fins of a male. I did spend some time looking at the tanks of male and female fancy guppies to see if I could tell on adults. I also read that female anal fins are more a fan shape whereas the male anal fin is longer and more pointed. Is this correct? I just brought them home and put them in the QT until the neons leave tomorrow. It could just be that they are stressed and not letting the anal fin extend... We'll see.

If anyone has good pictures of a younger male/female pair, I would appreciate it.

Also, how old do you think they are? They are about 3/4" long....

I have no idea about guppies. I decided that fancy guppies would not work with my betta and neither would these long finned blue danios the lfs had... so we compromised with these guys...

Thanks!

-TM
 

ishar

ishar

MFT Staff
#5
Jul 27, 2007
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Hamilton, ON.
#5
Well my guess is that that are about two to three months old at that size.

And just in case you misunderstood, the anal fin is the one right by their anus, not the big one at the very back. All fry have the same looking one before maturation- it is sort of curved and of proportionate length. Once the males mature this fin becomes very thin, longer, and becomes mobile. The females stay the same as when they were fry but grow with the body and become fan shaped, yes.

EDIT

I found a link for a picture of an adult ale's gono.- they look exactly the same when they are fry to.
Gonopodium
 

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T

trailmule

Large Fish
#6
Jan 2, 2008
126
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#6
ishar - as far as I can tell all 4 look like the picture. I also read that male feeder guppys are a bit more colored than the females who are always a dull brownish. Here is the best picture of a guppy similar to mine. I will try and take pics of mine later. http://i36.photobucket.com/albums/e38/Ash3333/guppy.jpg

The coloring is similar....

At what age to male guppies mature? When I can say for sure that they are male or female...

Thanks for all your help. Never had guppies before, but I think I like these little guys...

-TM
 

ishar

ishar

MFT Staff
#7
Jul 27, 2007
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36
36
Hamilton, ON.
#7
I have found my fancy guppies to mature at roughly a month or so of age. However I believe I have read that feeder guppies mature faster than fancy ones. If they look like the picture I posted then they are definitely males. If you had a female and a male beside each other you would have no doubts :).

When my first fry matured it was like one day they all looked the same, then BAM- I wake up and look in the tank the next morning and one of them had a gonopodium and the other had a fin. These things develop very rapidly once the male matures, and there is not much mistaking it.

Congrats on your four males :)
 

T

trailmule

Large Fish
#8
Jan 2, 2008
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#8
Excellent! I have no desire to have fry swimming all over the place. Although I am sure my female betta would love the snacks.

Being feeders, should I leave them in the QT for awhile? I looked over the rest of the tank at the lfs and none appeared sick. But that doesn't always mean everything's okay...

Also, how big do they have to be to not get sucked up in the filter? I have a AquaClear 30 and I would hate to lose them in the intake tube. Should I put something over it? Part of a nylon stocking perhaps?

Thanks!

-TM
 

ishar

ishar

MFT Staff
#9
Jul 27, 2007
1,490
0
36
36
Hamilton, ON.
#9
Well I have fry in all sizes from newborn to near adult, and I lose so few to the filter I don't even worry about it. I used to but it was such a pain to cover it all the time and it reduced the flow so much. If yours are as big as you say there is no way they'd fit through the grate of the intake tube opening and get sucked up. That and the fact that they are now strong enough swimmers to get away from the suction they will be just fine.
 

OdeToBlitzkrieg

OdeToBlitzkrieg

Small Fish
#12
Dec 15, 2007
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Tennessee
#12
Are you sure you don't have Endler's guppies? They're a species that tend to be very small. The picture you linked to looks very similar to an Endler. If they are Endler's, you probably got a good deal, because they are anywhere from $5.00 to $10.00 a piece. Here's a picture.

 

MissFishy

MissFishy

Superstar Fish
#13
Aug 10, 2006
2,237
5
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Michigan
#13
Without reading through this whole post...the one way to tell male/females apart at the earliest point is to look for gravid spots on the females. Any fish with a darker region behind their stomach is a female, the males will not have a gravid spot. The gnopodium doesn't start developing until much later. It is good to seperate males/females at the earliest point, then the fish will grow bigger and more colorful as opposed to just focusing on making baby guppies. There's some more info on my website linked below.
 

T

trailmule

Large Fish
#14
Jan 2, 2008
126
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#14
God this is complicated! =)

MissFishy - these are not fancy guppies, but colorful feeders. They all have a base color of silver with irridescent spots of black, red, or greenish. Two of them have black spots near the anal fin. They are small and don't particularly like to sit still for me to examine them....

Here are some pics that look similar to mine
BBC News | SCI/TECH | Fishy clue to promiscuity
the first fish here
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Erfurt Wild Guppy - GuppyWiki

Similar but not exact. Perhaps I will leave them in the QT until I know for sure. I think their all male but.....

TM
 

T

trailmule

Large Fish
#18
Jan 2, 2008
126
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0
#18
Yeah they are just normal male feeders.... But I think they are cute! and pretty...... They add a little bit color to the tank - with all the plants and the drab corys, the give a little shimmer here and there...


-TM
 

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