Sorry Sue. It hurts to lose them, especially the ones you've had a long
time.

As to why you lost fish this year, there are several possibilities. One -
they grew. You may not have any more fish in number, but if their total
length was factored in due to their growth, it's the equivalent of adding
more fish. One 18" fish requires a whole lot more than 3 6" fish. As to
why you lost the larger ones, that's classic oxygen deficiency. Especially
if you found them dead in the morning. Smaller fish have less oxygen demand,
so they can handle the shortage better, which is one of the few times that
smaller fish have it better than larger ones (it's normally the other way
around: larger fish are stronger).

NitrItes are resultant from the filters kicking back in: ammonia --
nitrIte -- nitrAte. You can use ammonia binders to protect the fish from
that, so you get a Zero ammonia reading, but the filter is still processing
it. The next step is the nitrIte, then nitrAte. Usually nitrIte poisoning
can be controlled with salt - as little as .15 ppm will avoid brown blood
disease.

I don't think your larger fish died from nitrItes. It was probably oxygen
deficiency - or perhaps something else. NitrItes also damage the gills -
little fish have less gill surface and will show the effects more quickly.
They're still alive. Keep the airstones going: I've never heard of a fish
that died from too much oxygen in its water, but I've known plenty that died
from too little. It can only help.

Again, sorry for the loss of your babies. It hurts.

Lee


"SueAndHerZoo" wrote in message
news:MUT9c.2098$9g.1660@lakeread04...
Hi. If you recall I wrote about a week ago with my koi hiding and dying.
Some of you suggested nitrite poisoning, which made sense, and when I
tested
the water, the nitrites were high. I have been doing water changes,
adding
salt, firing up the pump and filter, added 2 more airstones, etc. and the
water tests fine now. Unfortunately, I lost 4 of my very large, "been
with
me from the start" koi. I still break down and cry a lot, especially
when
I'm out working on the pond, and most people think I'm nuts, but I knew
people here could relate - they were my "babies", I raised them from only
a
couple of inches long, they ate out of my hand, followed me around the
pond,
etc. Of course a part of it is the guilt - I feel as if I killed them
or
let them down.

But anyway, sorry for the venting, here are my real questions: why is it
I
still have quite a few small fish and koi fry that survived, and only the
big ones didn't make it? I thought it would be the other way around with
nitrite poisoning. And secondly, I still need to know WHY I had a nitrite
problem this winter - it's never happened before. It would be easier to
deal with this and prevent it from ever happening again if I knew WHAT I
was
dealing with. Thanks for letting me vent - nice to know there's a place
where I can cry over fish and not feel like a fool.
Sue