I keep mine in a white plastic bucket with a lid on top. They keep indefinitely.
I just keep them in a cardboard box in the garage. It can get humid here in the summer and they stay rock hard. No problem with ants, maybe due to the vinegar? So, I would say just store them in a way where ants and other pests won't get into them. J
I store mine in a plastic storage bin with the lid on. A bin that does not have any openings for air and clamps shut. I put wax paper in the bottom then in between each layer of sugar bricks then on top of last row. That keeps them nice and solid. You can store them in the house or in a garage. I wouldn't recommend anyplace that is high humidity like in a shed or garage with no heat. I do the same with cookies at Christmas with the wax paper and a metal tin container. They last forever and don't get stale. That's how my German Mom did it and it worked.
I pulled the remains of sugar blocks off my hives yesterday and switched to sugar syrup. My question is can I reuse the blocks next winter? Can I mix them with next year's batch and if so how do I do that since they are rock solid? It seems like a shame to simply throw away the uneaten pieces of blocks.
If you're feeding syrup just use them for that. Otherwise I have kept them sealed in a plastic bag in a chest freezer (may not be necessary) and used them the next year with no issue.
Thanks, but I don't understand your comment: If you are feeding syrup just use them for that. Do you mean re-liquify them?
Yes any I have left when I do use them get turned into syrup for nucs .
Break them into tiny pieces, first? Just put them in the feeder and add syrup, like an ice cube?
Is there a water-to-brick formula to re-liquify? I'm sorry I'm being a little dense today.