Sexing my pair of JD's

[Netminder3]

This is a 9 inch and 7 inch pair of jack Dempsey's. I think the larger one is the male but not sure...

 

[fishorama]

Yep, you got them right, small female, big male. Short more rounded fins = female; longer more pointy fins - male.

Be careful, they can lay 30+ eggs at a time every month & them what? We bred a few cichlid species in the "olden days" & it was hard to even give them away after a while...& we were not trying to save fry to raise separately. It's fun a few times but have a plan...the larger & more aggressive the fish the harder to sell/give away...

 

[Netminder3]

Came home today to find my EBJD male and Blue gene JD female surrounded by fry.

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[fishorama]

Congrats on the fry! That looks like a different male, lol. Very pretty! Is the other male in the same tank? It will be trouble!!

If you want to try raising fry remove the male after a week, he'll have lost interest in fry care. The female will be ok for maybe 2 weeks. Or have a grow out tank to move the fry into. But like I said have a plan, this is just the beginning!

 

[Netminder3]

This is a completely different tank. I plan on moving the fry out today to a grow out tank

 

[fishorama]

So, what female was mama? An electric blue like pretty papa? I'm not sure how the genetics works for them.

 

[Netminder3]

If you look towards the back you can see her she’s very dark right now. Blue gene female JD

 

[fishorama]

Sorry, I just did a quick look at your pics. Now I see her in the 2nd shot. I don't know EBJDs, they weren't a "thing" back in my big cichlid days. So does she just carry the EB gene? Granted, she's not the focus of your 2nd pic, but she "looks" like a nicely colored "regular" female. Maybe female don't express the "electric" gene like your male? I'm not being critical, just wanting to learn...so we can all learn.

& I always like fry pics...I'm going to need more as they grow please!

 

[Netminder3]

The male is an electric blue Dempsey. The female is a standard jack dempsey with the blue gene. This is the best way of getting EBJD fry that will survive and more percentage of EBJD fry vs regular JD. Putting 2 EBJD together is not the way to breed. The fry normally don’t survive and if they do they are sterile most of the time.

 

[fishorama]

Ah, I knew there was some genetic issue with electric blue fish of any species, not just JDs (acaras, rams, etc). I didn't know it extended to sterile fry! That's not good...But it is good you know!

All I can think ATM is the Mendel's punnett square of inheritance. But with less good outcomes. I recently read an article on the "electric blue" trait & where it "might" have come from. As I recall it's not like the easy mutations of long fins, albinism or balloon bodies (ewww! NO! Not this!) to selectively breed for. I'm sorry I didn't save the article (or at least where I can find it).

If you know more about this can you please share? Not in terms of your fish (although that would be great)...but just in general? I'm feeling very rusty on genetic inheritances...