We have a formation at the bottom of a small run off that looks like a pond in our sheep paddock. It has a culvert under the drive into the swamp on the other side, it hasn't had water in it for the last year as we havn't had enough rain to keep it full. If I was to line it would I be able to keep goldfish in it or would the run off with the chance of sheep manure be too polluted, and what would the chances of the goldfish escaping into the culvert and into the swamp? I could probably put a mesh grill over the hole.
I built a pond at our old house and it was a machine, I started with 4 fish and ended up with heaps and couldn't count them all in the end with my water lillys taking off and oxygen weed and some other ferny thing growing like weeds and snails multipying like rabbits. It was fun going down every couple of days checking out the 'new' pond. Although I would be restricted in the plant I plant as it does run off into a swamp which then turns into a stream, which I have seen fish and fresh water crays in.
Cheers
Glenn