When Do Guppies Become Sexually Mature? Question 

Caroline J

Valued Member
Messages
247
Reaction score
55
Points
38
Experience
Just started
Hello! So my pregnant guppy gave birth last month on the 26th. They've been growing pretty rapidly, and I've loved taking care of them. I divided my 20 gallon tank for them, and recently I've been thinking a lot about inbreeding. Obviously I'd hate for this to happen, so I've been doing research on it but some websites say guppies can reproduce as early as 1 month old. Is this true? I'm freaking out a bit to be honest. If it is true, I don't have much time before they'll start to breed. But surely at 1 month old, the adults could still eat them right?? So I wouldn't be able to separate them by gender. I don't have another back up tank. I'm not quite sure what to do. To be honest, I'm about done with guppies. I mostly had them to build up a well established tank. And I truly would miss them, I love them all so much and they're such personable fish. I definitely understood what I was getting into with having males and females in the same tank, but I think at this point it's mostly just the fact that I'm ready to move on to more experienced fish. Hopefully I can find loving homes for them or sell some. Oh well, I'm just ranting at this point. I appreciate any replies or help! - Caroline
 

Dillan Murphy

Valued Member
Messages
452
Reaction score
60
Points
38
Experience
5 years
Yes they become sexually active a 1 month. I have endlers they are closes related to guppies. My male was tiny and was still trying to breed my much bigger female endler.
 
  • Thread starter
  • Thread Starter
  • #3

Caroline J

Valued Member
Messages
247
Reaction score
55
Points
38
Experience
Just started
Dillan Murphy said:
Yes they become sexually active a 1 month. I have endlers they are closes related to guppies. My male was tiny and was still trying to breed my much bigger female endler.
Gosh, that's insane. Would I even be able to sex them at 1 month?? I suppose at this point that's the only thing I'm worried about. I could find a tank to separate the males and females, as long as I can tell their sex by then. And thank you so much for the help!
 

Dillan Murphy

Valued Member
Messages
452
Reaction score
60
Points
38
Experience
5 years
They should be starting to get their colors at a month old but some males take awhile to get their color. For males look at the analfin the fin on the bottom if it has a point it is a male.
 
  • Thread starter
  • Thread Starter
  • #6

Caroline J

Valued Member
Messages
247
Reaction score
55
Points
38
Experience
Just started
Dillan Murphy said:
They should be starting to get their colors at a month old but some males take awhile to get their color. For males look at the analfin the fin on the bottom if it has a point it is a male.
Thank you so much! I'll definitely be looking out for that. I appreciate your help.
 

GuppyDazzle

Well Known Member
Messages
1,059
Reaction score
947
Points
148
Experience
More than 10 years
One month is when they say guppies can possibly breed, but I've never seen any guppy breed at a month old. However, it is good to start worrying about it at a month. You need to separate males and females if you want to continue to produce fancy guppies. If you just let them breed, their colors will dull and they'll get much smaller after a few generations.

At about a month old you can start to sex guppies. Personally, I look for females in the fry tank (gravid spot) and move them into a female-only tank. I'll continue to do that between about four and six weeks. That way I know the female-only tank will have all unhit females. There will be some females weren't recognizable after six weeks or so, but after that I worry they'll be hit, so I don't put them in the female-only tank. I put them in a community tank. That way I end up with a tank of males, and a tank of females. I try to be really careful not to put any males in the female tank. I've wrecked whole tanks by accidentally putting a male in who gets together with the females before I know he's there.

If you're not concerned with keeping and breeding the fry, you can probably just let them breed and the adult fish will keep the population down

If you only have a couple tanks, breeding guppies really isn't going to work. It only takes two to produce 30 or more fry every month. Once the fry start maturing, if you don't have them all separate, you can do the math and see why they call them the "millions fish." I love breeding guppies,but they take so many freaking tanks. I recently set up a fish room with 23 tanks so far, and I can only keep a couple lines.
 
  • Thread starter
  • Thread Starter
  • #9

Caroline J

Valued Member
Messages
247
Reaction score
55
Points
38
Experience
Just started
GuppyDazzle said:
One month is when they say guppies can possibly breed, but I've never seen any guppy breed at a month old. However, it is good to start worrying about it at a month. You need to separate males and females if you want to continue to produce fancy guppies. If you just let them breed, their colors will dull and they'll get much smaller after a few generations.

At about a month old you can start to sex guppies. Personally, I look for females in the fry tank (gravid spot) and move them into a female-only tank. I'll continue to do that between about four and six weeks. That way I know the female-only tank will have all unhit females. There will be some females weren't recognizable after six weeks or so, but after that I worry they'll be hit, so I don't put them in the female-only tank. I put them in a community tank. That way I end up with a tank of males, and a tank of females. I try to be really careful not to put any males in the female tank. I've wrecked whole tanks by accidentally putting a male in who gets together with the females before I know he's there.

If you're not concerned with keeping and breeding the fry, you can probably just let them breed and the adult fish will keep the population down

If you only have a couple tanks, breeding guppies really isn't going to work. It only takes two to produce 30 or more fry every month. Once the fry start maturing, if you don't have them all separate, you can do the math and see why they call them the "millions fish." I love breeding guppies,but they take so many freaking tanks. I recently set up a fish room with 23 tanks so far, and I can only keep a couple lines.
Thank you so much for the advice! It's was all very helpful. And oh my God a whole room dedicated to tanks of fish is a dream. Honestly just an entire room or even multiple dedicated to animal care would be incredible. But you're definitely right, guppies are such a huge hassle solely because of how often they breed. A lesson learned the hard way, I suppose. I'll try and find loving homes for all of them, but I'll make sure to inform everyone just what they're getting into if they insist on males and females in the same tank. It's been a joy to keep them, and this was a nice way to ease me into the hobby but I think now I'm ready to go on to more advanced fish. I'll just have to figure out what to do with these guppies. Hopefully a lfs will take some. I'm going to miss them quite a lot, although. But it's for the best. Again I appreciate your response!
 

GuppyDazzle

Well Known Member
Messages
1,059
Reaction score
947
Points
148
Experience
More than 10 years
My wife was a grade school teacher and had animals all over the place (now retired). We had a room in the basement that had lizards, rats, gerbils, Madagascar cockroaches, you name it, during the summer. She was the crazy animal teacher at her school and I know she gave the principal headaches, like the time she found a newborn mouse on a trail on a field trip and nursed it back to health with kitten's milk every two hours, but now I'm rambling.

I'd set up a 10 gallon tank in her classroom every year with guppies and some other kinds of fish. That's where I saw the results of really frequent water changes. The kids did the tank maintenance, and it was a lot more fun than doing math and stuff, so they did water changes like every day. I cringed thinking about all the grubby hands stuck in the water, probably wild swings in the amount of water conditioner added, and variation in the temperature and percentage of the water changes. And it was the healthiest tanks I've ever seen. Frequent water changes cannot be stressed enough, unless you have lots of plants that are absorbing the toxins.

Your LFS will take your guppies. If you get a few more tanks, you can be a bit selective with your breeding, and they'll buy them from you.
 
  • Thread starter
  • Thread Starter
  • #11

Caroline J

Valued Member
Messages
247
Reaction score
55
Points
38
Experience
Just started
GuppyDazzle said:
My wife was a grade school teacher and had animals all over the place (now retired). We had a room in the basement that had lizards, rats, gerbils, Madagascar cockroaches, you name it, during the summer. She was the crazy animal teacher at her school and I know she gave the principal headaches, like the time she found a newborn mouse on a trail on a field trip and nursed it back to health with kitten's milk every two hours, but now I'm rambling.

I'd set up a 10 gallon tank in her classroom every year with guppies and some other kinds of fish. That's where I saw the results of really frequent water changes. The kids did the tank maintenance, and it was a lot more fun than doing math and stuff, so they did water changes like every day. I cringed thinking about all the grubby hands stuck in the water, probably wild swings in the amount of water conditioner added, and variation in the temperature and percentage of the water changes. And it was the healthiest tanks I've ever seen. Frequent water changes cannot be stressed enough, unless you have lots of plants that are absorbing the toxins.

Your LFS will take your guppies. If you get a few more tanks, you can be a bit selective with your breeding, and they'll buy them from you.
Agh, I absolutely love that idea!! Although I must say my dad would refuse to visit me if I cared for Madagascar Roaches. But they're very interesting creatures, and I love that she was comfortable enough to take care of them! Aww that is so sweet. See, that's would I'd love to do. Have a room or two dedicated to nursing animals back to health of any size. And haha I love rambling, so that's no problem at all.

Ooh, that rather does make me cringe a bit, but I love that the kids did tank maintenance, I feel like that could teach them responsibly and you're definitely right, it's a nice break from math! I bet it was very educational as well. As long as it was healthy, they did a wonderful job.

I sure do hope they take them, I messaged them yesterday and today so they should get back to me tomorrow! I'll see what their policy on that is and all. I greatly appreciate your advice and stories.
 
  • Thread starter
  • Thread Starter
  • #13

Caroline J

Valued Member
Messages
247
Reaction score
55
Points
38
Experience
Just started
BettaFishKeeper4302 said:
I've never heard of 1 month, i always heard 3 months.
Hmm interesting. See, I thought I had around 2 months or so, but it seems many more people think 1. I suppose I'll go with it and see what happens! I greatly appreciate your answer
 

Guppy_Lover713

Valued Member
Messages
139
Reaction score
68
Points
38
When I had baby guppies 8 were born. 2 died, and from the other 6 I figured out 2 were females about a month in due to the gravid spot that was developing on them. Around that same time I suspected 2 of the guppies were males, but couldn’t confirm. About half a month later I was able to confirm 2 more females due to gravid spots and 2 males since they weren’t getting gravid spots, they were more colorful, and their analfin was changing into a gonopodium. Strangely my males have not been very interested in breeding yet.:emoji_shrug:
 

Mcasella

Fishlore VIP
Messages
8,416
Reaction score
4,383
Points
458
Experience
5 to 10 years
My most recent males were mature enough at 5 weeks that you could see a gonopodium almost completely developed, I pulled them out at 4 weeks old because they were starting to develop.
Feeder guppy males can be fully developed as early as 1 month, most fancies take a little longer (but more experienced breeders can id the signs of a developing male and get him moved earlier than someone who doesn't have the experience).
 

emeraldking

Well Known Member
Messages
1,532
Reaction score
1,413
Points
248
Experience
More than 10 years
It's true that guppies can be sexually developed already within a month after birth. But they won't be that large. But becoming sexually developed doesn't mean that they'll be eager to mate right away.
 
Toggle Sidebar

Aquarium Calculator

Follow FishLore!





Top Bottom