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  L# Black Sludge/Algae Problem
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SubscribeBlack Sludge/Algae Problem
kj fishy-finn
Big Fish
Posts: 385
Kudos: 200
Registered: 21-Jan-2004
female usa
EditedEdited 10-Jul-2011 18:01
I wrote this thread last summer pertaining to this problem:

I did end up performing a black out for several days and that helped, but I'm not sure that helped eradicate the problem entirely because I'm still fighting it. I've been out of town for several months with the tank being cared for with water changes etc.

I've tried starting live plants several times in this aquarium only to have them die off. Last summer, it was because this black slime choked them out. All I have left is a Cryptocoryne becketti which is managing to survive even with its leaves coated in the stuff.

Should I try another black out again?

Would adding aeration/oxygen help?

Once I get it under control, would the best approach be to heavily plant the tank and hope the plants take off and choke out the algae? What would be the reason my plants keep dying off?

Sorry if this post was a bit confusing and I'm trying to ask a lot of questions, but I'm frustrated with it.

kj fishy-finn <*)))><
20 Gallon Album
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Post InfoPosted 10-Jul-2011 18:01Profile PM Edit Report 
Small Fry with Ketchup
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Registered: 17-Apr-2003
female australia us-maryland
Eh algae issues are frustrating, I'm right there with you on it!

Especially BGA.

Having, as you can guess by my reaction to BGA, dealt with it before in a number of my tanks the only thing I found to work was antibiotics. I did a number of total black outs trying to remove as much of the algae by hand before doing the blackout. Then repeated the process a few times before giving up and going the medication route (I think it was tetracycline). Between that and adding nitrAtes to the tank I didn't have problems with it again (though I didn't have the tank for much longer as I was moving).

Doing another blackout may work, I know it's hard when it's the slimy smelly stuff but if you can try and remove as much as you can from wide leaves it would help. I found a papertowel worked fairly well and a good gravel vac to get any floaty bits up.

What are your tank readings, especially nitrAte? I had BGA rear it's ugly head the moment my nitrAte dropped too low, which is why I had to search long and hard to find potassium nitrate at the hardware store (sold as a stump remover it's pretty hard to find since it's also used to blow things up ). How much light per gallon, how old are the bulbs, do you know what the kelvin rating is (sometimes written on the bulb itself). Do you CO2?

The plants themselves need additional CO2 above about 2wpg of light, anything else the algae gets to first. Keep in mind that oxygenation/aeration/surface agitation drives CO2 out of the water.
Additionally the plants need some nitraTes in the tank, otherwise they're going to struggle.

Sorry if I've gone over stuff you already know, or has been said in the other post already, didn't have a chance to read all the way through.


Post InfoPosted 20-Jul-2011 04:22Profile Homepage AIM MSN PM Edit Delete Report 
Posts: 5108
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Registered: 28-Dec-2002
male usa us-colorado
Hi Kim,

The only problem with using antibiotics is that it kills
or weakens all bacteria including the colonies that manage
the Nitrogen Cycle. So, if you use them, plan on recycling
the tank.

Blacking out a tank, and or using the antibiotics will do
no good in the long run unless you tackle and remove the
underlying cause of the BGA. Water changes are great, but,
you also have to vacuum the gravel in the tank, clear down
to the glass bottom. Since the tank is in the condition
that it is in, I'd take out the surviving plant, clean it,
and then put it in some water for a day or two while you
work on the main tank.
You can use either the black out or the antibiotics, and
then, after the treatment(s), thoroughly clean the tank.
Perform massive water changes sucking up the
dead/dying algae, first. Then refill the tank and do the
gravel cleaning throughout the tank, while doing another
massive water change. Then Refill the tank, stick an
airstone or two in the tank, crank up the filter and
start removing any detritus in suspension. When all is
done, do another massive water change (dig a hole in the
gravel down to the glass bottom and drain the tank down
to the glass), refill it, put your token plant back in
the tank and start the cycling process.

Below are some links that might help.


-->>> The Confidence of Amateurs, is the Envy of Professionals <<<--
Post InfoPosted 20-Jul-2011 15:20Profile PM Edit Delete Report 
Small Fry
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Registered: 29-Aug-2011
male usa us-iowa
EditedEdited 08-Sep-2011 02:51
in ENCYCLOPEDIA OF AQUARIUM PLANT by Peter Hiscock he advises a siesta time for the lights to "slow" algae growth. iv "painted" the diagram in this book. the staggering of lights creates an artificial sunrise/sunset instead of a sudden light/dark. according to this book your plants start photosynthesizing quicker than algae.....might not help but wouldnt hurt trying right good luck

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Post InfoPosted 08-Sep-2011 00:22Profile PM Edit Delete Report 
kj fishy-finn
Big Fish
Posts: 385
Kudos: 200
Registered: 21-Jan-2004
female usa
Sadly, I just tore down this tank for the next year. I'm away at school and I just haven't been able to give it the attention it needs so I did something I should have done a few years ago.

When I set it back up, I will have to keep this in mind and set up my lights accordingly to help prevent this problem in the future hopefully.

Thanks for the wonderful answers though!

kj fishy-finn <*)))><
20 Gallon Album
5 Gallon Album
Post InfoPosted 08-Sep-2011 01:31Profile PM Edit Delete Report 
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