Re: How do you "keep" queens?
I store queens in 4 frame nucs. I wish I had 5 framers as that would be so much easier. A 4x2 queen castle is useless other than using to mate virgin queens in, two frames is not enough to store queens in unless you want to have to manage it twice a week or more, and even then, it's just so problematic. I don't even like the idea of using two frames as mating nucs, it's just not enough, in my opinion. I say mating nucs need 3 frames as a minimum. I advise to avoid the 4x2 queen castles.
20+ years, raise my own queens, feed when needed, I treat but have not perfected varroa management yet.