Darkness: how long to kill algae?

[Marc Goldstein]

Hi everyone,

I've done a lot of reading at the krib and other places about dark
treatments to kill off algae blooms. What I'd like are some recent
practical experiences from this newsgroup. The general concensus from
what I've read suggests about 4 days, but I would welcome any experiences
that relate a practical darkness time frame to killing specific kinds of
algae.

I'm just passing 3.5 days of darkness in my tank, but the light
green beard algae seem to be still present in force. Tonight, at 4 days
of darkness, my plan is to go in and remove by hand as much of the algae
as possible, hoping that it will be largely dead (I'm an optimist).
Before the darkness, I pulled as much of the stuff out as I could from
the plants. Peeking in with a tiny flashlight last night I could see
there was still lots of algae all over the tank.

Any thoughts on this? I'm hoping to gradually bring the tank into balance
so as to minimize further algae growth, and think I have balanced light
and CO2. I know what to do with nitrate based on recent experiences that
lead to the bloom, and my phosphate is quite low (~0.05).

Thanks in advance.

Marc

[mark]

I am doing the same thing. I have somewhat of a neglected tank that had DIY
co2 and 56watts of power compacts. Recently it went through a serious bloom
of the light green cottony strand type of algae. It took over java moss and
had begin to grow over the swords. So far I have have left the light off for
5 days, then cleaned out the dead algae(turns a darker green color, like
green slime in horror movies), and turned one light back on(28watts) and am
running no co2. So far about 70-75% of the algae is gone. The fish and
plants made it through ok. I plan to use co2 again after about another week,
until then this darkened down tank with no co2 seems to be finishing off the
algae. I am hoping the plants show signs of renewed growth soon accomanied
by the death of more algae, then I will add co2. I noticed that premature
use of co2 when the plants are not at an optimal growth rate tends to just
bring back the algae.
m

[Marc Goldstein]

In article <3895DD93...@netscape.com>, ma...@netscape.com says...

> I am doing the same thing. I have somewhat of a neglected tank that had DIY
> co2 and 56watts of power compacts. Recently it went through a serious bloom
> of the light green cottony strand type of algae. It took over java moss and
> had begin to grow over the swords. So far I have have left the light off for
> 5 days, then cleaned out the dead algae(turns a darker green color, like
> green slime in horror movies), and turned one light back on(28watts) and am
> running no co2. So far about 70-75% of the algae is gone. The fish and
> plants made it through ok. I plan to use co2 again after about another week,
> until then this darkened down tank with no co2 seems to be finishing off the
> algae. I am hoping the plants show signs of renewed growth soon accomanied
> by the death of more algae, then I will add co2. I noticed that premature
> use of co2 when the plants are not at an optimal growth rate tends to just
> bring back the algae.
> m

Thanks for your reply to my post. If my algae outbreak doesn't come under
control I will try the 5-day treatment.

As it is, I did a 4-day treatment (absolute dark, minimal CO2 just to
keep the pH stable at 6.8, and lots of water changes). After this amount
of time, the green water was much-diluted; the water was nearly clear.
The thready beard algae all turned red (I'll post a separate message
about this), and I've been pulling it out. I don't think it is dead.

Now I'm back at full lights and CO2, with nutrient supplementation that I
am hoping will eliminate the original problem.

Marc

[CloneZero]

Why would you assume that the algae would disapear after 4 days. YOu,
hopefully, have managed to kill it. It should turn read-ish in another
day or two. After a week or two it will drop off, plus your fish will
start picking at it. They it will disappear and get sucked in to your
filter. They it will be all gone.

If you have live plants you need to let them have a week or two of
light before you do another black out. They have probably used up
moost of there reserves. Be patient, if in a couple of weeks the algae
is still green, black out the tank again.

Eric

* Sent from RemarQ http://www.remarq.com The Internet's Discussion Network *
The fastest and easiest way to search and participate in Usenet - Free!