Oh, I've been doing my homework, or rather, the fish have been "doing it"
I've raised guppies and glofish (unexpectedly on the glofish) before, but never bettas, and currently raising my first betta fry. It's a dry (wet) run. I want to see what mistakes and successes I make, learn from them, before breeding my better quality fish.
This is Jazz, the Delta tail, and his mate, Betty Boop the Halfmoon (she's the one sporting red eyeshadow and lipstick):
Their coloration carries the "jumping marble" gene. They switch color weekly, it seems.
I used your method, auban, only in a clear plastic shoebox with a heating pad under it. Put Betty Boop in a betta cup for a day in the shoebox. They did the nasty continuously for 10 hours when I released her, but neither got nasty-very minimal damage.
Here are the fry, they were free swimming March 9th, so they are about 2 1/2 weeks old. Sorry for the crappy pics. Dried leaves are banana from my tree.
There are about over 100, and I dutifully turkey baste the waste daily. Been feeding microworms and just added fine powdered fry/betta food. Finding about 2 dead a day-don't know if this is normal? Haven't posted this until today, because I don't want to jinx them, lol. Being my first betta brood, it's been nerve-wracking, and you might think the eggs came out of me!