If you use just fruits it may work. But IN MY OPINION you MAY wanna dust that up with something that prevents mold growth... and fruit flies like humidity though.. You may be onto something thoughthanks for the link crysta
I'd breed fruit flies but the substance is always a pain, I've never gotten it right. It's either too watery, or molds, and I'd rather save money than buy the premade kind. I wonder if just fruits will actually work, haha.