I recently put up a 4' chain link fence, then had to take it down.. Dog pen, dog gone now lol...
I had tamped dry bag mix in the holes as I plumbed the post.
The moisture in the ground did set the concrete and they were set well enough that 3 of the 10 corner/gate posts broke off rather than come back out of the ground. I only used 1/2 of an 80 lb. bag per post.
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