Thats the same way my Bettas are. Even if I feed them first, they wonder to the bottom of the tank and see the food and take it. I did have 2 catfish on each side of my divided 10 gallon. Yesterday after taking 30 minutes to try to catch my bettas (damn thing know now if they see the net to hide in the plants) I decided to put all 4 of the catfish on one side of the tank. I need to buy a breeder tank. How long do you keep the Bettas in the breeding tank for and how much/how often do you feed the catfish?
It takes Tango about 15 seconds to eat 6 pellets. It takes the corys 15 minutes to eat one pellet broken in half. Then Tango chased the corys away from their own food and carried it away. He was so bloated and sick from it, I had to separate him. He would have eaten himself to death.
The breeders cup is maybe 7 inches long, three deep, three wide? My tank is 16 gallons high. It has one divider, so you can put two in it.