Whitefly? in the GH. Help!

Ooooh, you may have hit it on the head. The white bits I'm finding are thrip sized, but whilst there are the occasional greenfly, nothing in numbers that reflect the qty of white bits. I must find the opportunity to put the white bits under a lens to see if they move. Uncovering this morning I took any peppers with suspect insects outside, gave them a shake and flicked them to see if anything fell off in the wind. It did, but not all I'm afraid.