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Nnewworld said, age/size makes a big difference in appearance. Venting will be most accurate, but even then it’s hard when the fish is still small and immature.
I have no experience w trimacs. I would have said 1M1F judging by the dorsal tips, though I would have said
Nnewworld ”female” was a male by the very pointy dorsal.
At the size yours are, even venting is very difficult unless you can get a magnified image.
Patience grasshopper
Here is a 4.5 to 5" female.
Note the color in the dorsal.
Below the same female (in spawning color), with a male
You' can see the dark blotch of the female as she nears spawning time
One thing you may want to consider, is the influence of the bright, white substrate, that tends to wash out the cichlids normal colors.
It causes cichlids attempt to blend in., and that doesn't make IDing gender characteristics any easier