I have set up a new couple to spawn. He is a crowntail she is a doubletail, they were both conditioned for nearly three weeks on extra hikari pellets, frozen blood worms and frozen brine shrimp.
This will be my second spawn so I did what worked last time, put him in alone for a week, then added her. He flared at her, she ran (swum?) away, he chased her for awhile. She did quick fly bys of the half styrofoam cup, saw that there were no bubbles and darted back into the plants. He flared at her some more and she flared back! Well that stopped him dead in his tracks!!
I removed her then, and stole some bubbles from my other males and replaced the half cup with just a piece of styrofoam. He came on over and checked out 'his' new bubble nest.
The next day I put her back in but this time I left her in her jar. He flared and wriggled his butt all over the place. She did seem impressed so after 24 hours I released her AGAIN.
Now it is 24 hours later, he is hovering under the bubbles, she is patrolling the tank. She comes right over to him and the nest and butt wriggles at him and does the head down clamped fins posture but he just chases her away.
Oh well at least there is no damage of either of their fins, he is much too slow to catch her and she just wants to breed!!
I might up the temp to 84 F, it is at 80 -82 F at the moment. As I am in Tasmania, Australia I have no easy access to IAL, but I did add extra Blackwater extract.
How long should I leave them before I give up on that cross?

3 to 4 days. Leave them alone and do not touch the tank. LOL ;)

LOL, Ok I will leave them alone. ^_^ It is stressful watching them. He is now hearding her around. He can get her under the nest but he dosen't know what to do with her when she is there!!
Oh well, at least she isn't freaking out at his constent flaring, she is just going where he directs her. She has a few rips to her anal fin so he got her a couple of times. She is all barred up and is acting very mellow with his behavior.
Cross your fingers for them?