My L1 Chinese ate like that for a couple of days when my cultures were at a low point. They're molting to L5 now, so I think you should be good! I also fed mine a couple of tiny ants, or any bug smaller than they were I would at least offer to them.
Putting bits of fruit in different areas in a tupperware that I could quickly close when I saw it had flies got me a couple dozen. If I thought I had some flies in the container, I'd pop it in the freezer for two minutes and see what drops.
There was also a night where I set up a white bedsheet on a clothesline with a super bright light right next to it. I got more leafhoppers than I needed, but the setup was inconvenient for me so I didn't do that again.