I know the Zett's family.. nice folks, but the advice they gave you is
incorrect.
I have 2 farm ponds.
Initially I had the same problems as you (back in 1982- 1984), and I used
herbicides (simazine).
Then I thought about what I was doing and went "natural".
I bought a number of lilies (from Zett's actually), and planted marginals
(water irises), waiting a year to allow the simazine to dissipate (there are
studies saying it accumulates in soil).
Within 3 years the ponds (which have no significant spring feeds) totally
cleared up!
I have them stocked with lge mouth bass, perch, rosey red and fat head
minnows, and crayfish.
I love Koi, but they stay in my gunnited water garden/Koi pond, as they keep
the water much too dirty (as they are benthic feeders and constantly root
around in the mud) in a farm/mud pond.
Good luck,
Greg


"Dave" wrote in message
om...
Hey everyone,

We own a farm that has a 2 acre pond on it. The pond if fed from 2
springs we have on the property, and is 30 feet deep (yeah, it's
pretty big).

There are probably 200 or more Koi in the pond, ranging from
fingerlings to giant 2 foot long monsters. There are also abundant
minnows and we've even spotted a couple of catfish.

Now for the problem: The pond water every summer gets green and
stinky. Even when I can see by the outflow that water is still coming
into the pond. Since it is a dull green color, I can tell that it is
probably algae. When the dogs jump in the pond they always come out
stinking to high heaven.

The fish don't seem to mind this much, clearly they are reproducing,
and they obviously survive the Winter. Every Spring, the pond
explodes with frogs and tadpoles, so we got the amphibian angle
working there too - but for humans, it sure isn't much fun to
contemplate swimming in green stink water.

I've tried Cutrine Plus (last year) and it knocked down the matted
algae, and cleared the pond up a tad, but I'm looking for a better way
to keep this pond clean and clear. I'd love to find a better
"balance" for the pond with something to eat the algae, but there is
just so much of it, and I have no idea what kind of creatures I can
put in there to create a clean ecosystem.

I've got Zetts catalog - but when I called them, the guy on the other
end of the phone just told me to buy more Koi - "but I've got hundreds
already" I said. "Well, just buy some more" was his answer.

I've even considered having a buddy of mine who lives in Michigan ship
me some Zebra Mussels - they cleaned out the Great Lakes! (this is a
joke, folks).

Can anyone tell me what I should do to get this water clean and clear,
and not stinky anymore?

Thanks!

Dave.