[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

RE: [APD] Variation on green water -- little green threads

Kurt Wiedenhoeft wrote:
> I'm still fighting the green water fight, but over the last couple of
> days I've noticed something that I didn't see before. When I look very
> closely at the water, I see that there are short strands of
> green algae
> floating in it everywhere. I would say one cc of aquarium
> water probably
> has 10-20 strands in it. They appear to be maybe 1/4" long, straight,
> and very thin.

It sounds a lot like Spirogyra however Spirogyra threads can get several
inches long. There are several hundred (thousand?) species in this
category of algae and I have a couple of tanks that are infected with
it. It can travel from tank to tank on equipment, fish, snails, plants
or your hands.

I have discovered that antibiotics will kill it however it is much
easier to employ an extended black out of about a week to kill it. First
clean the tank thoroughly removing as much as possible mechanically.
Cover the tank completely to eliminate any stray room light & leave it
in the dark for about 7 days. It might be gone in a shorter time but
I've found it best to use a lengthy black out. Its also wise to do a
complete water change & thorough vacuuming after the black out to remove
any spores. You'll know the algae is dead when all the stringy bits have
rotted away.

I think its a good plan to have some hungry snails, especially pond
snails, to eat the rotting algae. By vacuuming up detritus & snail
feces, you eliminate sources of organic pollutants especially organic
phosphate, which algae can feed on. Pond snails seem to be better algae
eaters than Ramshorn snails.

If you are relying solely upon plants for O2 for the fish, then its wise
to add aeration to the tank or to move the fish to a darkened quarantine
tank for the duration. My quarantine tank is placed under a table & has
cardboard around it to prevent sunlight or intense light from hitting
it. I use biological filtration in this tank, which is otherwise bare.
Its too dark for algae to live in over a long period of time. Paul K
uses coarse gravel in his quarantine tank so that feces & algae can drop
down into it.

After the thorough cleaning & water changes, you'll want to re-dose with
all mineral nutrient so that the plants can take off again. Those plants
with stored reserves such as Anubias, Crypts and others with rhizomes,
will continue to grow in the dark although new leaves may be yellow,
they will green up with nitrogen. You can still have nitrate in the
water, which I believe the plants can take up in the dark however the
plant must use stored reserves of energy to perform these biological
activities. Thomas might comment on N uptake without light. I think I've
read literature to support N uptake in the dark but haven't made a study
of it.

You should be able to find lots of pictures on Google of Spirogyra to
assist in identification. An alternative might be Oedogonium which is
like peach fuzz and can reach a few millimetres in length. Oedogonium is
readily dealt with using bleach treatment & tank sterilization. I don't
know much about how long it can survive in the dark. A 7 day blackout
might also work on it. I have some other filament algae that I want to
try killing with an extended blackout.

Steve P in Vancouver where my cherries are getting red! Already snitched
a few... :-)

Aquatic-Plants mailing list
Aquatic-Plants at actwin_com