Fry and adults

emeraldking

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Too often it is said that all livebearers grab their young and eat them. But that really does not apply to all livebearers. You can get many species get used to those tiny tankmates. But it usually takes time to get to that point.
Here is a video with guppies of mine. This refutes the generalization that all livebearers eat their young if they get the chance. And of course there are also plenty of species that do eat their young. But again, it doesn't apply to all livebearers.
 
Look at ‘em all ! Guess that myth just got blown out of the water . Pun intended .
I can send you some airline tubing if you need it and then you won’t have to have that Tower of Babel thing going on with your sponge filter . 😅
 
I find that fry eating relates directly to tank size with most livebearers (and killies, their relatives). There are a few livebearer groups that are ferocious cannibals, for certain. But most ignore their fry (but here, seemed to eat the fry of other species). I've had huge colonies of variatus, swordtail species, platy species, molly species, guppies, etc.

In a single species tank at least a metre/yard across the front, the average livebearer only eats the occasional one of their kids.
 
Hello. I've always had a considerable number of fry from my live bearing fish. I try to provide a lot of floating plants and when I notice a larger than normal female, I start to feed a bit more than normal. It has been my experience that well fed adults show little or no interest in the fry.

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@10 Tanks Try keeping some Brachyrhaphis livebearers some time. They are some of the most resourceful cannibals outside of nightmares. Pretty fish though....
 
I got a pregnant, currently giving birth, guppy in her own 3 gallon tank. There's been a small fry popping out of her for a while now so I'm hoping it's just a slow birth to start. I think this is the first time she's given birth. I removed her from the main tank earlier today and haven't found any fry in that larger tank. I guess we'll see if she eats her fry. I've been feeding her and she's been eating in the small 3 gallon.
 
I think it’s also about population sizes and bioloads. There was a paper about this that I read and could never find again. They put different numbers of adult guppies (from 2 to 100) in about 20 identical tanks, and after a few months every tank had (more or less) the same number of adults (50ish). In the ‘understocked’ tanks they didn’t eat (many) fry, but in the overstocked tanks they did.
 
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@10 Tanks Try keeping some Brachyrhaphis livebearers some time. They are some of the most resourceful cannibals outside of nightmares. Pretty fish though....
Hello Gary. I'd love to have another tank and get some fish that are more unusual. However, I'm trying to control the population in the tanks I have now. Purchasing more isn't an option for me. But, I'd love to do it!

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Hello Gary. I'd love to have another tank and get some fish that are more unusual. However, I'm trying to control the population in the tanks I have now. Purchasing more isn't an option for me. But, I'd love to do it!

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lol Brachyrhaphis They can turn and eat their fry almost as fast as you can blink an eyelid
 
I’ve seen one of my female P/K class Endler’s Livebearers go after some of its own fry :rolleyes:
Although I have not actually witnessed it eat one yet.
 
I find that fry eating relates directly to tank size with most livebearers (and killies, their relatives).
It's one of the causes. But again, there are livebearere species and strains that leave fry alone no matter what.
Hello. I've always had a considerable number of fry from my live bearing fish. I try to provide a lot of floating plants and when I notice a larger than normal female, I start to feed a bit more than normal. It has been my experience that well fed adults show little or no interest in the fry.

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If you're aware of it that your fish do eat fry then yes, it would be better to give them some hiding spots. But if they don't no hiding spots needed.
@10 Tanks Try keeping some Brachyrhaphis livebearers some time. They are some of the most resourceful cannibals outside of nightmares. Pretty fish though....
True! They're beautiful fish but recentless fry eaters.
I think it’s also about population sizes and bioloads. There was a paper about this that I read and could never find again. They put different numbers of adult guppies (from 2 to 100) in about 20 identical tanks, and after a few months every tank had (more or less) the same number of adults (50ish). In the ‘understocked’ tanks they didn’t eat (many) fry, but in the overstocked tanks they did.
Yes, but when it differs every time in those tanks, there's still no hard conclusion to make wether those guppies used are real fry eaters or not. And if a tank is really, really overstocked, nature helps you out by letting a number of fish die (no matter the age). And then it's not a matter of fish getting eaten but Mother Nature is taking care of the problem. That's normal. For the bioload becomes too much.
 
So you just let Nature control the population? I'm already worried about all the (adorable) fry appearing. I've seen adults approach them, but they are REALLY fast and dart out of the way. I can't get any more tanks. How can I teach the adults it's OKAY to eat them? I'm going to give the first batch away if I can catch them, but I have 2 females, and they're both healthy.
 
Try feeding the fish less. They’ll get hungry and turn to other sources of food…
 
So you just let Nature control the population?
Well, in lots of tanks overhere all fry grow up to adults. Like I've already mentioned not all livebearers will eat fry.
Try feeding the fish less. They’ll get hungry and turn to other sources of food…
Not in my case. Most tanks with several kinds of livebearer species are so used to those small fry that they leave them alone. Livebearers like Brachyrhaphis species for instance will eat their fry.
It's a fact that not all livebearers will eat fry. But as I've already have mentioned before, there are also livebearer species that do eat their fry if they get the chance. I'm doing this for a number of decades now to stand by my remark.
 

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