Sexing Jack Dempsey

I have moved my One of my Jack Dempsey into a tank on his own as it is just not the same size as my others and after a recent ram casualty iv moves him into his own 3ft 35g tank I have two and wonder if I have a breeding pair so he could have a tank mate ? Can any body sex these I thought two males but I’m not sure

they aren't Jack Demspeys. bottom fish looks like a gold edge rivulatus (green terror). no idea about the top fish.

Your joking , 100% not Dempsey as I will return them to their breeder , I bought them well over a year ago and when they were 1-2 inch I would never of said not Dempsey I wouldn’t. Of spotted they were not Dempsey now tbh what gives it away

A breeder said they were Jack Dempseys?? Yeah.... avoid that person in the future. They aren't even the same fish.

Bottom is a Green Terror. That is 100%

The top fish looks like a regular blue acara. Blue acara are not as popular as they once were since the Electric Blue Acara has come around. https://www.seriouslyfish.com/species/andinoacara-pulcher/ They can look a lot like green terrors but the body shape is different. I'm fairly certain the top is a Blue Acara.

What gives it away? A jack dempsey looks like this.....clearly not these fish.

That’s clear to see now , iv had the fish from small and wasn’t very coloured I had them off the same breeder that sold me peacock Malawi for a differnt tank and turned out to be a mbuna hybrid thing , is there anyway to check the license numbers of these breeders ? And finally question if one is acara and the other Green terror why is the acara so aggressive I have a pair of electric blue acara n they are dopey but this one is very aggressive not just a nip to say get out of my cave it will actively chase the other fish

The Electric Blue acara is more peaceful than the regular blue acara.

This somewhat supports the theory of one of its origins that it is a possible hybrid of an electric blue ram and blue acara. As we all know, rams are peaceful.

Cichlids are aggressive fish and each one has its own personality.