I use DE, you don’t need to use food grade, just the poultry one. I use it in my hen house to control red mite. It is a very fine powder and quite tricky to puff on the plants. I tried it out on some aphids in the tunnel and then rinsed it off a few hours later, I am a bit concerned about harming rove beetles and ladybirds so did not want to leave it on too long. It did seem to work. The flea beetle thing is a well known way to deal with them, brushing along the tops of the plants with a bit of cardboard with vaseline on captures them as they jump up and you can go over them a couple of times a day until you have reduced the numbers, guess if you catch a few makes you feel better:)