"Kevin" wrote in message
ps.com...

Sounds like your pond is coming along really nicely...If algae scum is
your only problem, consider yourself lucky.

It sounds like your pond has alot of nutrients and with all the sun,
you have gangbuster algae growth.

* Yes. It's been unusually hot here as well. And all the fry are adding to
the nutrient load. There are only 4 semi-adult koi in the pond with all the
algae problems.

You note that you fish are growing at a great clip. I wonder about how
much food your putting in. In addition to the fish growth could
overfeeding be a source of nutrient overload? With the tropical
climate, I suspect you might have to be careful with plant nutrients.

* Overfeeding? No. All the food is gone in under 10 minutes. This 800g
pond has had algae problems for the last few years, even after we drain it,
hose the liner and plants and wet-vac the bottom, then refill. Last summer
we did it twice and the algae was back in no time. We have no idea what's
causing it. We even rebuilt the berm thinking it was a runoff issue. It's
not. I have a 1200gph pump in the lowest part to suck out what settles
there every week - that hasn't helped at all.

I have also found that certain plants grow faster better than others.
Lilies and certain other plants look great but don't add alot of mass
and thus I'm not sure how much of a "nutrient sink" they are. I have a
couple of pots of Elodea in my pond and they grow really quickly and
give a great bushy look. I also imagine they're really soaking up lots
of the excess nutrients. I think my papyrus is doing the same, as it
adds lots of growth.

* Some are better than others for sucking up the nutrients that's for sure
but koi will destroy some plants. We're starting to think maybe the Tetra
filter we have on this pond is inadequate. But that can't be the whole
problem. There's always bits of black stuff floating in both ponds that the
pumps aren't picking up. The fish stir it up into blackish clouds at
feeding time. That's another problem. When looked at under the 'scope they
appear to be parts of decaying plants that settle everywhere.

Finally, I'm guessing that the algae, etc. might be first-year growing
pains. Once the system settles down a bit, I imagine it'll all work
itself out. However, if you're in a tropical country, you may face
different challenges than I do in Chicago.

* I'm down here in zone 6 and this pond is now 11 years old. The 2000g one
is 9 yrs old.

Good luck

Kevin
--
KL....
Frugal ponding since 1995.
My Pond & Aquarium Pages:
http://tinyurl.com/9do58
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