Oxymel of Squill wrote:

If it's a new pond I suggest leaving it at least a month before
putting in plants and then another year before introducing fish. Maybe
that's a bit ott and people in this group laugh at me for it, but it works.

It does seem like overkill. A friend had offered me 3 good sized koi,
so 2 days after filing the pond, I introduce fish (the 10 cent each
feeder goldfish). Within a week they all had died. I introduced 5 more
feeders and when they were all doing fine in another week, I added the
koi. It has been close to a year now and the koi and those 5 goldfish
are all doing fine. So, your mileage will vary. I'm lucky to have a
well, so there are no chemicals in the drinking water and the PH is
just slightly on the basic side.

Dave

http://members.tripod.com/~Vid eoDave/pool/pool.html