I had the same problem you have, but worse. I researched up a storm when I decided I wanted to breed bettas, and I was all set. I mean everything was perfect. However, my male and female became friends...and nothing more than that. He is probably about 7 months old, and was 5 months old when I first tried spawning him. He never built a nest until last month.
Thats when I tried spawning again. Complete flop. No nest, no interaction between male and female, nothing. Then one day I put Stella in Abes bowl to see if the space was just too big. BINGO- that was the trick. Yet, Abe is a slow learner as you can tell, and he didn't know what to do with the eggs. He ate a few to make sure they weren't food, and ignored the rest.
On my newest attempt (now that they actually KNEW how to spawn), I had to use a different female because Stella was not conditioned, and Pepsi was. So in Pepsi went with Abe in the normal spawning tank. I was about to cry because I waited 1, 2, 3 days and than the next morning, got to witness them spawn. They spawned from morning to late evening. Abe AND Pepsi would both pick up the eggs and place them in the nest. THey did not eat a single one. Today I just noticed that my fry have hatched and Abe is being the perfect father.
So, all in all (sorry for the loooong example) you just have to try everything and keep trying over and over. Abe's instincts appeared in a flash, and your male's might too. You can also try to mix match your bettas. Try the male with a different female, or the female with a different male. Whatever works for you is the best way. I used to think that betta breeding was like a recipe: 1 spawning tank, 1 male, 1 female, 1 sponge filter, water, heater, mix and enjoy! For some, it just happens that way, and for others (like me) you have to try a million and ten times just to get them to blow a fricken bubblenest, lol! (BTW, Abe's nest is actually a nest from my other male that I had to transfer in there, lol! But don't tell him that!). Okay, this is long enough now, lol. Just a few words of encouragement
Alexa
