I'm not sure if the bottom one "Beto" is a male? Are they both males? I looked around on the web to distinguish their sex and i read that males have the red line on the top fin and that the top and bottom fins are pointy on the end and they have brighter colors. Well they both have that....what u guys think? Their color intensity changes a lot and they both seem to have the same coloration even if in the pic it looks a little different....Beto(the bottom one) chases my o's around even if he is a lot smaller. Pepe(the top one) defends the o's and chases Beto around. Pepe does chase Beto a lot and puts him on his corner, Beto doesn't fight back that much, but he sure fights with the o's and corners them hehe.

Oh and don't mind my lush brown algae background lol... i draw on it ones in a while haha

Males have larger, longer and pointed dorsal and anal fins. Females have smaller, shorter and more rounded fins. bottom could be male, but i wouldn't put money on it. )

that looks like 2 males to me.

smdsatx wrote:


from the pic you have posted the top looks male and the bottom one is female.
nice pair you have there.......

no idea on sexing dempseys im afraid but just posting to say thats a lovely pair of fish!!

agree with necromancer4
top is male, bottom is female.

The way to tell now is by the spots below their eyes. From all the hormone food issues, you cant really depend on dorsal fins anymore unfortunately

Males have spots that do not extend to the jaw area, and stop right below the eye, females obviously the opposite, they have spots that extend all the way down to the jaw. your pic is not clear for me to be 100%, but look at them based on that
criteria, but it looks to me like the bottom one had spots all the way down.

this is still not 100%, but is the most common way to tell the difference.