Hi Fish Addict
I've only kept Paradise Fish,Bettas,and Kissing Gouramis in the past. But I'll try to help.
First question I have is are you sure you have a male and female. From the website recommended above for gourami breeding the males seem to have a pointed anal fin as well as pointed dorsal. Your pics. look to me as if the small one has more pointed fins.
And from my experience breeding both Bettas and Paradise fish I have seen the female take on a more masculine role and make bubble nests. You could have the sexes reversed?