Need help sexing nicuraguan cichlids

[steve p]

Hi, can someone confirm if i have a pair of nicuraguan cichlids or two males, I bought them as a pair but since i've had them im not so sure. Sometimes they get along with each other then out of the blue the larger one (which i think is the male) will chase the smaller one relentlessley around the tank for a couple of minutes.

Steve.

[Nolapete]

Smaller looks like a male, the larger a female. Notice that the females colors are more subdued. Hard to tell on the female's dorsal fin, but from what I can see it has more rounding than the male's even though it has the streamer on the top.

[Jmerk]

On the second pic down, the bigger fish is FEMALE and the other, more colorful one is MALE...