As far as having fish in your pond. You can't keep fish OUT of your pond. If you have a 2ft. diameter puddle that never dries up (like a spring) you will get fish in it. I've seen this dozens of times over the years and have always wondered how.

One example, we have a wet weather creek that cuts through my property. We have had a pretty extreme drought the last 3 years, and it had been almost 2 1/2 years with never enough rain to make it even trickle, no water in it at all. Late this last year the drought finally broke and it ran and filled up. This is only fed from the bar ditch alongside the road. This spring a couple of deep spots that hold water were full of small perch. I don't know, maybe their eggs dry up and can still be viable years later, like those shrimp eggs you used to get in the science kits. Other people have said fish eggs stick to the legs of wading birds (I don't buy that!) Maybe even the birds are smart enough to stock new territory by releasing fish on purpose.

Anyway, I would be more surprised if you didn't have fish in a pond that size.