Hey guys, I have a probably dumb DIY question. I’m looking at putting up a short length of fence using 4×4 posts, and the concrete calculators are suggesting I will need 6 50lb bags of concrete per post (since the hole should be 3x the post diameter, and there’s 3ft of post below ground). This seems like an insane amount of concrete to me. Would I be able to get away with 3 or 4 bags per post, filling up the hole to whatever level that reaches, then backfilling soil on top to fill the rest? The fence doesn’t need to hold back a herd of rhinoceroses. We have very sandy soil if that changes things! Thanks.