Black Out To Kill Blue Green Algae

ebrcknrdg

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I have BGA on the substrate in my tank so im going to try a blackout to get rid of it. On another forum Tom Barr writes....

Turning the lights out and covering the tank so that it is completely
dark with a blanket/trash bag etc works in 3 days. Doesn't cost a
thing.
Do a 50% water change, remove as much of it as you can and add 1/4
KNO3 per 35 gals of water, then do whatever treatment you decide on.
When it's done, do another 50% water change and add the same dosage of
KNO3.
Keep up on nutrients, filter cleaning from now on. It or some other
algae will always come back if you do not take care of the plants and
have them grow well.

How do i measure a quarter KNO3 per 35G? I have 33G of water so what measurement of KNO3 do i need?

Ill post before and after pics so i can show if it works or not
 
I have BGA on the substrate in my tank so im going to try a blackout to get rid of it. On another forum Tom Barr writes....

Turning the lights out and covering the tank so that it is completely
dark with a blanket/trash bag etc works in 3 days. Doesn't cost a
thing.
Do a 50% water change, remove as much of it as you can and add 1/4
KNO3 per 35 gals of water, then do whatever treatment you decide on.
When it's done, do another 50% water change and add the same dosage of
KNO3.
Keep up on nutrients, filter cleaning from now on. It or some other
algae will always come back if you do not take care of the plants and
have them grow well.

How do i measure a quarter KNO3 per 35G? I have 33G of water so what measurement of KNO3 do i need?

Ill post before and after pics so i can show if it works or not
keep us posted I've gone down with the dreaded blue green too
 
//bga is a bacteria and not an algae
the best ways to cure it are
A ) a course of anti-biotics, like acriflavin
B ) place a copper coin in your filter for a week or so.
 
//bga is a bacteria and not an algae
the best ways to cure it are
A ) a course of anti-biotics, like acriflavin
B ) place a copper coin in your filter for a week or so.
DONT put a coin in if you have shrimps you WILL kill them and contaminate the tank permanently meaning you cant ever keep shrimps or marines in it.
 
I'll dispute that point

pesonally I have cured BGA with a copper coin in a tank that housed nothing but cameroon armoured shrimp and angels
and all survived the treatmnent.
now I'm not saying that all shrimp will survive, just pointing out that not all shrimp are the same

as with any copper based treatment the onus is on the aquarist to deem if s/he should use it or not.
 
Use Chucks calculator to work out the amounts and dose a minimum of 10ppm KNO3 into the tank before the blackout, after the blackout do a large water change and dose the KNO3 back in again. Dose 3x10ppm KNO3 each week from then on if using EI method for fertiliseing.

I would try a blackout first of all, if that does not work or it returns then try the anti biotics, but a blackout will cost nothing and could work for you.

Good luck.
 
I did a 4 day blackout on my BGA (one day extra for good luck) by covering it with binbags. I didn't dose any nutrients at all and when I uncovered the tank I couldn't believe how bright it looked without the BGA. I then did a big water change and reduced my lighting from 4 on 2 off 4 on to just 6 on straight. For about the first month I had a small amount of residue on the front glass and top of substrate and every few days I wiped it off using a credit card between the glass and the sand. Since then it has cleared up completely. I left the tank completely untouched for 3 weeks when I was on holiday and the glass was sparkling when I got back.

If the blackout had not worked then I would have moved onto anti-biotics which I read are very effective, I think you have to buy them in packs of 100 but someone on here who has bought a packet may be kind and sell/give you a few.

Try the blackout first though.
 
dose a minimum of 10ppm KNO3
Good luck.

Need to get my head around this one :blink:

If I had a 1 million litre tank, then I would dose 10 litres of KNO3, yes?

OK, so I have a 100 litre tank, so I dose 1/1000th of a litre? ie 1ml ?


Good luck Emma, the blackout will work; just hope the BGA doesn't return. It always does with me.

The copper coin sounds interesting. Might give it a go.

I've been cultivating BGA for several years now; and never been able to eliminate it.
 
//bga is a bacteria and not an algae
the best ways to cure it are
A ) a course of anti-biotics, like acriflavin
B ) place a copper coin in your filter for a week or so.

Curious to where you would get anti-biotics from in the UK. A copper coin may well work but is far from a fail safe method and would highly recommend against this method.

Don't know why everyone goes to so much hassle and expense when all that is needed is a three day blackout. If done correctly it is 100% effective and causes no harm to anything except algae and bga.

If the cause of bga isn't fixed then no matter what method you use it will come back again.

James
 
Use Chucks calculator to work out the amounts and dose a minimum of 10ppm KNO3 into the tank before the blackout, after the blackout do a large water change and dose the KNO3 back in again. Dose 3x10ppm KNO3 each week from then on if using EI method for fertiliseing.

I would try a blackout first of all, if that does not work or it returns then try the anti biotics, but a blackout will cost nothing and could work for you.

Good luck.

Im really no good at working this out. Ive tried the calculator but i cant get my head around how much KNO3 ill need?

For EI method (low lighting low co2) im going to be dosing 15Ml KNO3 3x per week. So how much will i need to dose before and after the blackout?
 
Use Chucks calculator to work out the amounts and dose a minimum of 10ppm KNO3 into the tank before the blackout, after the blackout do a large water change and dose the KNO3 back in again. Dose 3x10ppm KNO3 each week from then on if using EI method for fertiliseing.

I would try a blackout first of all, if that does not work or it returns then try the anti biotics, but a blackout will cost nothing and could work for you.

Good luck.

Im really no good at working this out. Ive tried the calculator but i cant get my head around how much KNO3 ill need?

For EI method (low lighting low co2) im going to be dosing 15Ml KNO3 3x per week. So how much will i need to dose before and after the blackout?

If you add 102 grams of KNO3 to 500ml of water this will mean that for each 1ml of that solution = 1ppm of NO3 is added to your tank, so 10ml of that solution would be 10ppm etc.

15ml 3x per week sounds like a lot, 3x10ml 3x per week should more than ample in a low light setup provided you do 50% water changes each week to reset the tank.
 
We had a problem with BGA growing on our java moss so did a 3 day blackout a couple of weeks ago. We hadn't been using CO2 or ferts and had planned to start CO2 when the blackout ended but due to issues with the kit we won't be starting it till this weekend.

The BGA was gone when we uncovered the tank but the brown and hair algae were still thriving and we now have some manky looking brown hairy looking algae on the java moss instead of the BGA! It's been nearly two weeks now and haven't had any BGA back...yet!!

We dosed with KNO3 following the instructions on the Aqua Essentials website (mix 40g KNO3 with 500ml water and dose 10ml per 100l of water). Our tank is 240l so dosed with 22.5ml before blackout and the same after and have been dosing a couple of times a week. Hasn't had much of an effect on the nitrate levels according to the test kit though which says 10ppm before and after dosing!! So I am unsure if low nitrates is the reason why we had the BGA or not. We also added some RowaPhos to the filter as the phosphate levels were very high. I did read some research saying BGA can be cause by high phosphate to nitrate ratios but I don't know how true this is.

So now we have to try to solve our current algae issues - I'm hoping that starting CO2 and ferts will help but we shall see!
 
We had a problem with BGA growing on our java moss so did a 3 day blackout a couple of weeks ago. We hadn't been using CO2 or ferts and had planned to start CO2 when the blackout ended but due to issues with the kit we won't be starting it till this weekend.

The BGA was gone when we uncovered the tank but the brown and hair algae were still thriving and we now have some manky looking brown hairy looking algae on the java moss instead of the BGA! It's been nearly two weeks now and haven't had any BGA back...yet!!

We dosed with KNO3 following the instructions on the Aqua Essentials website (mix 40g KNO3 with 500ml water and dose 10ml per 100l of water). Our tank is 240l so dosed with 22.5ml before blackout and the same after and have been dosing a couple of times a week. Hasn't had much of an effect on the nitrate levels according to the test kit though which says 10ppm before and after dosing!! So I am unsure if low nitrates is the reason why we had the BGA or not. We also added some RowaPhos to the filter as the phosphate levels were very high. I did read some research saying BGA can be cause by high phosphate to nitrate ratios but I don't know how true this is.

So now we have to try to solve our current algae issues - I'm hoping that starting CO2 and ferts will help but we shall see!

You need a new testkit or have failed to agitate the B solution properly with your current one, you can reset the levels in your tank by doing a large 50% + water change and dose the known amount of KNO3 back in, tbh I have not used a testkit in so long I cant remember the last time I did! If you are not sure do a large water change and reset your tank levels.

Your nitrate levels probably bottomed out at some stage to trigger the onset of the BGA it has nothing to my knowledge to do with your high phosphate levels. Keep dosing the KNO3 and hopefully it will not return.
 
I've found that blocking light to the substrate/glass helps a lot to prevent BGA.

I think most BGA starts from the substrate.

Circulation issues are the next most common cause IME.

Then low NO3. But I think if you stop light from reaching the substrate depths i.e. through the glass, and sort out circulation, then BGA won't be an issue, even with low NO3.

Here's a shot of black tape around my tank. It may be coincidence but I haven't seen the slightest trace of BGA since using it. I used to see it regularly, ranging from very minor issues to whole tank wipeouts.

tapemz0.jpg


As for treating the symptom, the 3 day blackout works.

1. Remove as BGA much as possible first.

2. 50% water change and filter clean.

3. Blackout for 72 hrs. no peeking. Turn CO2 off. Don't feed fish.

4. Uncover tank. 50% water change removing as much crap as possible, clean filter.

5. Sort out cause of BGA to prevent re-occurance.

I'm not happy with the copper coin in the filter either. It may work for some but I wouldn't recommend it personally as there is no control over the dosing.

Source - D. Corkal, Canada PFRA, 2004

Copper (Cu) is a metal ion. Very small amounts of copper are essential for plant and animal nutrition. Some green algae thrive when copper is available as a micronutrient at concentrations of 0.03 mg Cu/L. Copper is toxic at high concentrations. For example, copper is poisonous to Rainbow trout at concentrations of approximately 0.04 mg Cu /L. Drinking water is regulated well below toxic levels for humans. The Canadian guideline is a maximum copper concentration of 1.0 mg Cu/L to avoid taste and staining problems.

Most water treatment products for algae control use copper as the active ingredient. The most common formulation is copper sulphate, often called bluestone. Many other commercial products are also available, but they rely on the same active ingredient. Some have additives to keep the copper in solution for a longer time period, increasing the treatment effectiveness.

Copper is toxic to most types of cyanobacteria at concentrations ranging from 0.06 to 0.25 mg Cu/L. When cyanobacteria are killed by a copper treatment, toxins may be released in high concentrations. Before using the water as an animal drinking water supply, wait at least 14 days after treatment to allow time for potential toxins to degrade.

Copper treatments work by dissolving copper into the water. When dissolved into solution, free copper ions will kill the target organisms - cyanobacteria The treatment will also kill or poison beneficial non-target organisms such as zooplankton and fish. Eventually, the copper will precipitate, settle, and accumulate in the sediment. Over time, copper and other nutrients such as phosphorus, will recycle from the sediment into the water column in micronutrient concentrations, especially in dugouts that are not aerated. Nutrients flowing into the water from runoff add to the problem and promote new algae growth, and recurring problems with cyanobacteria. This is a natural cycle for all dugouts.
 

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