Why is my male betta not makeing a bubble nest in his 10 gallon tank?

I have a female she is displaying the Verticale bars on her side, and my male is "showing off" to her but he hasn't made a bubble nest. Im trying the styrofoam cup idea as we speak. He has built one before in his .5 gallon tank. Ive even tried simulating one using bubble wrap. The temp. is in the 70's same with the outside temp. I have tried putting her in a jar and all he does is pay attention to her. Is he not building one simply because he thinks he still has on or what?