Betcha you've heard that question before...but I did read the FAQ.
Unfortunately, I still have green water and I thought I'd done
everything natural to cure it. I've finally got 75% of the surface of
my 3 barrels shaded with water hyacinth, water lettuce, and duckweed.
The WH has almost doubled in 2 weeks. Oxygenators are growing well,
with about 4 bunches in each barrel. I've got marginals in each barrel
too now - some are just getting started but the Acorus, fiber optic
grass, umbrella palm and canna lily are growing well. I also started
some watercress and it seems to be taking hold. My newly planted Iris
are breaking the surface now, and pickerel is getting close. I can't
see the water lily in the green water so no idea whether it's growing or
not.

I've tested the water and there's no ammonia, nitrite, or even nitrate.
pH is 7.4. I don't have a phosphate test. It seems I have enough
biofiltration. I have two of these 4" strainers
http://www.calpump.com/productsub.as...0T&category=10 on my
pump intake covered with their thick foam prefilters and filled with
bioballs. Actually one is half Chemi Pure and half bioballs at the
moment. I have about 65 gallons of water housing 3 2" shubunkins, 3
white clouds, 2 gambusia, and some ramshorn snails. The smaller fish
have been in the pond for a total of 10 weeks with the first shubie
added a little over a month ago.

The plants have apparantly finally sucked all the nitrates out of the
water, according to plan. The nitrate has dropped from about 5-7 ppm to
zero since I added the WH and duckweed. I've also been fertilizing
regularly with iron, trace elements, and potash the way I do fishtanks
to help the plants out. Even the green fuzz has slowed down to the
point that the fish and snails are keeping it lawnmowed. Bu the green
water keeps right on going.

So, I have shaded water, no nitrates, a TON of now nitrogen-starved
plantlife, hopefully adequte filtration and the water is still so green
and murky I can't see deeper than about 6". Fish? What fish?

I'm at a loss. Chemicals are not an option as I intend to eat my
watercress, and the cost of a UV unit is currently prohibitive. Do I
need more filtration, even though there's no ammonia or nitrite? Do I
leave things alone and wait now that nitrates are zero? Do I add
nitrate in case the plants are starved for it and can't outcompete the
algae? Should I try a flocculating agent? Help!

--
Elaine T __
http://eethomp.com/fish.html '__
rec.aquaria.* FAQ http://faq.thekrib.com