Re: NANFA-L-- Pond construction

Laura Burbage (leuhrich at
Tue, 20 Sep 2005 06:43:37 -0700 (PDT)

Date: Mon, 19 Sep 2005 11:45:49 EDT
From: Moontanman at
Subject: Re: NANFA-L-- Pond construction

I think you are right about filtration causing algae
sometimes. Or, rather, water movement causing blooms.
I think it's because blooms are often caused by
phosphorus. P becomes soluble in the sediment under
anoxic conditions (and I believe most everyones
sediment or debris has anoxic parts, even if they are
afraid of it). Water movement helps bring it up into
the water column (kind of like spring/fall turnover in
lakes). Likewise, it binds to particulates like clay
and organic particles. Water movement brings these
particles into the water column. While I don't have
the big outdoor ponds everyone's talking about (and
believe me, I'm drooling over them), I've experienced
such blooms when I decide to filter previously
unfiltered aquariums. Filtering got rid of debris,
but brought on the algae. Not that it's always bad,
some fish need the movement, but I have trouble in
some of my tanks.
-Laura B.

In a message dated 9/19/05 11:36:58 AM Eastern
Daylight Time,
dlmcneely at writes:

> i have lots of plants, mostly water primrose,
cattails, and sedges in
> my inground, lined pond. The pond is 12 feet long,
eight feet wide,
> two feet deep, filtered. i still have to harvest
filamentous algae
> periodically or they become a mass over the surface
and choking the
> primroses. i have mosquitofish and two longears
which i never feed.

I know this might not make much sense but I've found
that filtration
seems to
promote algae growth. After the first year the higher
plants became
established enough to out compete the plants. I don't
use pots except
when the plants
are new and then I use plastic mesh pots the plants
can grow out of. I
also use
lots of local snails and clams so that might make a
difference too
since the
clams are basically filter feeders.

My futures so bright, I gotta wear shades!
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