Message: 9
Date: Sun, 14 Nov 2004 06:55:30 -0800
From: "William M. Cwirla" <wcwirla at verizon_net>
Subject: [APD] Re: Green Water
To: aquatic-plants at actwin_com
As a long time lurker and occasional poster, I would like to relate my
recent experience with "green water." I recently moved a 29 gal.
classroom tank to another location. (Thanks, Karen Randall for the
inspiration to place tanks in school classrooms!) After a large water
change and the usual addition of potassium sulfate, the tank began to
cloud. Within 7-10 days it was pea soup green. In 28 yrs of keeping
tanks, I've never seen anything quite like it. Visibility was less
than an inch; the water was almost flourescent green. It seemed
"thick" to siphon and had that peculiar "algae" smell. Not dirty, just
green. Standing in a public place, the tank was a major embarrassment.
I searched the APD site and read the lengthy green water thread.
Initially, I tried aggressive water changes, but that seemed only to
make matters worse. I took Karen Randall's approach, which seemed the
least aggressive. I shut the lights off for five days. I didn't cover
the tank, so the fish could see with ambient room light. I installed a
HOT Magnum filter (great filter, by the way!) with its pleated micron
cartridge. And I did daily 10 gallon water changes (actually 2 five
gallon water changes).
At the end of the five days of darkness, the water was moderately
clear. At least I could see the back of the tank again. I continued
the water changes every other day for the next week. By the end of ten
days, the water had returned to crystal clear. The fish seem none the
worse for the wear. Actually, I think they rather enjoyed the green
and the water changes. The slow growing plants (Crypts, anubias) are
just fine. The fast growing plants (mostly hygros) showed some signs
of stress (red/brown leaves), but are fast on the comeback trail.
Why did the green water happen in the first place? I have no idea.
Too long since the last water change? Sudden influx of potassium threw
the nutrients out of balance? Unexpected change in tap water
chemistry? Who knows? I've long given up test kits and treat my tanks
like potted plants. They have a way of letting me know when
something's not right.
Moral of the story: 1. APD is the single greatest source of
information on the planet when it comes to planted aquaria. 2. Green
water happens, but it isn't the end of the world, or the tank. Be
patient. 3. Keep up with your weekly tank maintenance.
WMC