Okay, sorry it took me a while to get back to everyone, and thanks a bunch for all your help!
It was very greatly needed!
Well, "Howard" is doing MUCH better! He's waddling around and wagging his tail. Head is upright and checking everything out. Not very vocal, just kind of grunts still, but I don't think he was ever a very loud duck. I think he just needed a good long swim and an owner to learn about how to take care of a duck! I got his coop set up the right way now. (I hope) and I used a large soup pot. I buried it into the ground about 6 inches so he could easily dip his head under the water. Although I might have a fun time trying to get it out to change it. I guess I'll find out later tonight....
Now onto the answers to the questions...
Yep, he was my dad's pet that he's had since it was a chick. This was an only "child" but my dad got a plastic duck "playmate" that the real duck likes to sleep next to it and nuzzle it. So I made sure I brought that with me.
I knew this move would be stressful for him, but the way he acted when I first brought him home made me think he would bounce right back. He made himself at home right away! Then 24 hours later, I'm bringing him into the house and worried he might not make it through the night...
When he kept putting his head completely underwater in the bath tub, I was thinking, "Oh crap, maybe he's trying to kill himself!" (Obviously I know nothing about ducks!) Thanks for letting me know that's normal.
We do have a large run but putting the kiddie pool would take up at least half of it, and I don't think the hens would be very happy. So I'm going to take your idea with a stew pot!
The feed my dad gave me was layer pellets, I'm thinking he maybe didn't read the label because this is a boy. The feed I have is Purina Mixed Flock Granulates. It's for a chickens, turkeys and ducks. Pretty much all poultry. Then I mix in some scratch grains. (75% crumbles, 25% scratch) My dad also gave me a big bag of frozen sweet corn that I hand fed him some yesterday morning, but he wouldn't eat nothing last night.
Oh and sadly I know all about "clean water" for poultry. My chickens will poop in it within 5 minutes after I fill their winter waterers. I have to use the rubber bowls with a heater underneath to keep them from freezing. The summer waterers stay much cleaner since it has a hood. But even that gets pretty nasty by the end of the day.
I'll try to post a pic of him soon. He really is a sweet duck. I think he would make a good 4-H project for my kids! Out of curiosity, what is the average life span of a Pekin duck?
And Thanks again everyone for your help!