Hay should work fine for bedding, just realize that whatever you use, you'll have to change it out every so often to keep things clean.

The chicks are going to outgrow the Rubbermaid tub pretty quickly, so you have a second, larger brooder box planned? Also, sooner or later they'll learn to jump up and you'll find them perching on the edge of the tub. I use a chicken wire cover over my brooder box--chicken wire is OK for me because the chicks are safe inside my house. I use a large cardboard appliance box that I can get for free from behind local stores. :) Here's what my current set up looks like, this box is 47 in. x 27 in. and about 3ft. tall:

{{gwi:40503}}

The only thing to look out for with cardboard boxes is to make sure it didn't have anything toxic in it. The hardware cloth 'window' you see in the pic I reuse from year to year, I just hot glue it over the hole I cut in the box. I think it's essential to keep the chicks entertained and get them used to things moving around, it also keeps them from getting bored and picking on each other.

I wouldn't try the duck pellets for chicks. Try to find chick starter or grow mash at least (my feed store only carries grow mash). They might choke on the pellets, and the pellets may not have the correct nutritional balance for them.

We store our feed in 35 gallon metal trash cans with metal lids (vermin can't chew through them) and place a brick or large rock on top of the lid to keep rats & mice from getting in.

I've got a chicken info site here that may help, here's the section on hens & chicks:

http://jackshenhouse.com/VSChickHensBroodiesChicks.htm

Enjoy your birds, cochins are great! :)

Velvet ~:>