Mine clearly seem to be mating. The activity is between a larger (which I presume is the female) and a smaller (I guess is the male). The fish swim side by side with all fins extended and vibrating. Eventually the male rolls into the female and they break apart momentarily. They quickly resume the side by side position. They usually swim in the same direction (ie head to head and tail to tail) but occasionally they reverse and swim around in a circle. They continue this behavior for quite some time ( 10 – 15 minutes).
I was quite sure this was mating behavior because it was nothing like the territorial chasing that they normally do. In fact I didn’t think anything about it since fish are always mating in my tank.
When I went to look up the mating behavior of the SAE I found that it has not been reported!
I decided to check the fish out more carefully but every time I get close to the tank they duck into the plants and stop the behavior. I cannot confirm seeing any eggs yet.
I have two the exact same size, almost 3", and they do a strange dance every few days. They dart around together, sort of jittery and forward-back, like swordtails. They also circle each other, and when they do this their stripe fades away. One will roll towards the other. I had heard that they never breed in captivity also. And mine are so identical I would guess they are the same sex, but maybe not...?
I have 3 fish that range 2 1/2" - 3." They have clearly changed behavior from chasing each other around the tank to spending a lot of time swimming side by side through the dense plants. It is almost impossible to see what is going on in my planted tank; so, I cannot say if there are any eggs. I guess the only way I'll find out is if I see some fry.
I have 2 SAEs and have seen what appears to be mating behavior this past week. Both are approximately the same length. They get very jittery and then swim together circling each other, rolling, etc.
Before getting the second SAE, my first SAE would exhibit similar behavior with my female dwarf gourami which lead me to believe the SAE was a male. I am supposing the second SAE is a female but know it is difficult to determine gender. I've done some research. Not holding my breath for offspring.
I have also read that it is better to have sand as a sub-straight for SAEs to protect their underbellies. I have thought of adding some sand on top of the gravel. Any thoughts?