It depends on how big he is.
I feed mine full grown guy twice a day.
Usually 1 cube of tubafix worms each time.
I feed him guppies, 1 a day, give or take as I tend to throw in 6 at a time.
feeder goldfish once and awhile, I'll buy 6 and he'll eat em al in a week, so one a day or so.
I also feed mine reptile bites a few times a week, usually 2-3.
Basically feed him enough that his stomach doesnt begin to cave in, and not so much that it looks like he's going to explode.
If yours is a small one, I would feed him tubafix worms cubes, just break them up into small pieces first.
Oh, and I use a claw to feed my frog, works really well, you dont have to stick your hand in the tank and get your arm all wet.
**derek9305**
Your betta may harm your frog and vice versa.
If your frog is small most likely the betta will attack him.
If he doesnt, he will when he gets bigger.