I use 5 of those buckets for my 11 ducks. I've got them scattered all over their run. They are deep enough for them to stick their whole heads and necks in too. I always clean and refill them at night so if I know there will be a hard freeze I just put the covers on them and put them between my 2 pens which are under a tin roof. That helps a lot to keep the ice from forming.Thank you for letting me know! I could always ask my mom if we can use the laundry detergent buckets we currently have after they're used up. I think they're fairly big and sturdy. I agree: where I am, we've gotten maybe 3 days where it got down into the 40s this winter? It was cold enough for a little frost on the roofs the last two days, but now it's back up into the fifties this morning.
Not the best picture but my water bucket is against the post. I put the blocks of wood there so they can reach better.