Hey Bill, welcome to the forums!
We have been talking back and forth in another thread about aeration in the summer time and the affects of the heat throughout the water column. The thread is located here...
http://forums.pondboss.com/ubbthreads.php?ubb=showflat&Number=495553&page=1It is a bit of a read, but will tell you a couple things...
First off, aeration is no where near an exact science (and most of us are pretty green) and, secondly, small or shallow ponds can be adversely affected by moving water that has stratified (cooler deeper waters). Bottom Aeration can create water temps throughout the water that can get risky (too hot).
I would like to be able to say that surface aeration would be better for you, but I don't have any experience in that department, It is something to check into however. Typically for the pond hobbyist, surface aeration is used as an emergency effort to put 02 into the water. Surface aeration may stir a shallow pond up and cause the temperature concerns I mentioned too, so definitely do some research.
You should spend some time reading in the following two forums to get your feet wet...
http://forums.pondboss.com/ubbthreads.php?ubb=cfrm&c=6As far as electric or air lines to the pond... Either way is a lot of work, so I just threw the extra money at running electric and have not looked back. Eventually, I'll have a fountain, maybe a pump for watering the grass on the dam, night lights, etc.