I also have a 1,000 gallon pond that is plumbed to be filtered "just in
case" but the last 2 summers has not been. I built it primarily for a lily
pond and a fishless place for the treefrogs to spawn/breed. Once the
tadpoles are of good size and the temperatures are right I put 2 fantail
goldfish in, by the end of summer I have numerous babies. In the fall I
catch as many babies as I can to grow up inside and the rest are left to
survive the winter.
Come spring I catch the remaining and put in a stock tank, this year I had
13 in there, then I drain it completely to get the muck out. There is
enough muck after one season to fill a 5 gallon pail once it dries out, so
be prepared for that. The longer you let it go the deeper the muck will be.
The reason I mention fantails is, they are easy to catch, without draining
the pond and they don't over populate a pond like a couple of comets can in
one season. Of course not feeding them at all can help control numbers too,
but I think most here will tell you, not nearly enough. ;o) ~ jan
See my ponds and filter designs:
~Keep 'em Wet!~
Tri-Cities WA Zone 7a
To e-mail see website
I am by no means an expert, but I do have goldfish in my 1000 gal. pond.
From what I've read, goldfish need about half the room koi do - about 50
gallons per fish assuming each one will grow to 10" at most. Using that
formula 6000 gal. should accomodate 120 goldfish.
As for adding dechlorinators to the water - I added nothing to my tap
water when the pond was built. Just let it sit half a day and added my four
6" goldfish who are still alive 4 six months later! I have heard that
goldfish are more indestructible than koi though.
Hope this helps.