Live food is always a bad idea. Blackworms can carry parasites. I know because, I used to raise bettas and some would get very sick after being fed blackworms. You got your lei about the time that I got mine. I only feed mine hikari sticks and it has grown 3 inches. Hopefully it pulls through, and if it does, it will be better than ever. But you should really consider foodsticks/pellets instead of live food.