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Sex my jack dempsey plz!

Maxara Faxa

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Can you guys sex my jack? This one had the most spangles on its cheeks and is around 6" long. Picked it up from New Jersey and the aquarium shop girl swore to me it was a female. It was in there with 3 other jack dempsey that where looking kinda skinny. This one was thick...What do you guys think? 

I need a female jack to breed with my electric blue around 6"




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So... I am not a Jack keeper. Nor am I a "tank-buster" aficionado. I have one LFS who sells these a lot. I admire them, but lack the long wait to grow them to sufficient size to breed.

I do not have a definite answer for you. Here are some things to look for...

(1) This photo is a confirmed female Jack Dempsey. Notice how the lower part of her jaw and gill plate have a lot of the robin-egg blue...


(2) Now this below is a confirmed MALE Jack Dempsey. You'll observe that his gill plate is more spotted, and has less of the blue on the underside of the jaw...


(3) As you look at the pair below, notice that the male (upper fish) is darker (a spawning thing) and that the same general observations can be made between the blue spots on the jaw and gill plate with the upper (male) and the more developed blue casting on the lower fish (female)...


(4) Now, when a Jack is young, it is much more difficult to tell their sexes apart. Furthermore, when a Jack is isolated from others, and recently moved into a new aquarium, its colors may be all out of whack. Here is a young female...


You can see the start of more developed blue in the jaw and lower gill plate, but it is very light, and easily could be mistaken for a male.

Edited by Fish Folk
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Looks male to me.  Females develop a blue “beard” that is noticeable starting very young, and I could actually start to tell male from female in my fry by the time they were 2” long.  They were easy to sex by the time they were 3” long, and no doubts at all when they reached 4” long.

Here’s a pic of my pair, the female is the smaller and to the right of the male.  She has less prominent points on her dorsal and anal fins, less overall color, but shows the blue beard over her chin.



Your kiddo looks pretty stressed and not showing full color.  Should show a lot more color with time.

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Thanks for your replies guys! I'm definitely starting to think that it's a male. I took her out the tank and I couldn't help but take a look at her underbelly. I heard that it is a sure way of telling the gender.. except that I don't know what I'm looking for! Lol 

Here are the pictures regardless, if anyone knows please let me know! 



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