Where can I find the full blackout regimen?


Junior Poster
Dec 20, 2005
I've searched on blackout and BGA, but only found references to the full blackout regimen. Can someone point me to it or paste it here?

What I'm looking for is the specific instructions regarding water changes before or after, dosing before or after, CO2 on or off during, etc.



Guru Class Expert
Jan 23, 2005
Re: Where can I find the full blackout regimen?

if i remember right tom say's to change water 50% after good tank maintenence,turn off co2,and add a small amount of kno3 and po4.then after a three day blackout,change water again 50 to 75 % and dose macros.from my experiance this will not kill bba.good luck! regards,cornhusker

Tom Barr

Staff member
Jan 23, 2005
Re: Where can I find the full blackout regimen?

See Planted tank net, APC etc.

I've repeated it there a dozen or more times.
If you catch it early, you never have to do it, simply suck it up and irritate it, water change, then add KNO3.

If you got it bad, then the blackout.

50% before and get all of it off you can, clean filters, vac up old substrates if gooey etc, then blackout(cover the tank!!!! so that no light gets in at all) for 3 days and add the KNO3(1/4 teaspoon per 20 gal).
Turn CO2 off, aerate or increase circulation.

Remove cover, add light back, do 50% water change, Add KNO3 back and then there after, keep filters clean regularly. Remove extra circulation, add CO2 back, if you have plants at or near the surface, trim them back prior to any of this.

That is pretty much it.
Most failures are from: not doing the full 3 day, not covering the tank so that no light at all gets in, not adding the KNO3, during or after.

Some use the Antibiotics in conjunction or with the KNO3 so that it does not come back.

Either method works but the KNO3 and dirt issues where never addressed with the pills, the blackout helped to find the long term cure, thus no need for drugs thereafter.

Some clients don't want to do the blackout, so I had no choice, but I prefer the blackout personally.

If there is BGA after you remove the cover, you did something wrong.

Tom Barr