Here is my water:

Ammonia: 0 (as far as I can tell, the dip stick does not change color
and has no green in it)

There's your problem, dip sticks really don't catch small amounts of
ammonia. 2 bottle tests kits for ammonia are best, but check the expiration
date (especially on dip sticks).

Nitrites: 0.25

This number alone tells me that you've probably had/have ammonia in there.

Nitrates: 20
GH: 300
KH: 120
pH: ~8

Pond is 120 gallons, 3 2" goldfish in it. It's been up about 2 weeks
now, this is the second fish loss. The first one had no obvious signs
of disease like this one did.

The rest of your numbers are fine. As RTB has asked, what is the aeration,
is pump/filter running 24/7?

Don't feel too bad about the goldfish, especially if it was the feeder
variety, it is not uncommon to lose some. Don't buy or add any more till
the water clears up. Do not start over. Add some salt. 1 lb will give you
approx. 0.1% which will protect the fish against the nitrite and won't hurt
the plants, though you might want to take out some of the anacharis just in
case.

Pick up some ammonia detox, add it even if your dip stick says zero.
Especially if doing a water change. Ammonia detox chemicals usually also
dechlorinate.

Party time. Do 10% water changes using the Ammonia detox every day
before the party. This should help clean it up significantly yet not throw
off the cycling. ~ jan


See my ponds and filter design:
www.jjspond.us

~Keep 'em Wet!~
Tri-Cities WA Zone 7a
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