# Green Spot Algae - Increase Phosphate?



## kadoxu (28 Oct 2016)

Hi everyone,

Green Spot Algae is attacking my nano tank, mostly in the glass, but it seems to be affecting some plants as well. I'm probably to blame, because sometimes I forget to turn the lights off and they stay on for 1 or 2 ours more than they should with CO2 off.

What I've already done:

Raised water flow (by changing the spray bar to one with less holes in it)
Raised CO2 level
Started being consistent with light periods
Raised lights height
So now, my light period is about 7 hours. CO2 starts one and a half hours before lights on, and it stops 15 min before lights off. 

Now I want to raise Phosphate levels a bit, but I'm not sure if I should, and that's why I'm creating this thread.

My Macro solution mix is as follows:

1 tablespoon (tbs) of Potassium Nitrate
0.5 teaspoons (ts) of Potassium Phosphate
5 tbs of Magnesium Sulphate
2 tbs of Potassium Sulphate
1 litre of water
I dose 10ml 3x a week, so it should provide my 20L tank with something like:

Nitrate - 5.81ppm (17.43ppm weekly)
Potassium - 11.4ppm (34.2ppm)
Phosphate - 1.21ppm (3.63ppm)
Magnesium - 3.99ppm (11.97ppm)

So now I'm thinking about adding a bit more of Potassium Phosphate to raise Phosphates. 
Should I do it? To what level should I raise it to?


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## MrHidley (28 Oct 2016)

When i've had this problem, I've just increased my macros knowing that will increase phosphates, rather than mixing a new solution.


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## john dory (28 Oct 2016)

I reduction in light seemed to work for me


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## Courtneybst (28 Oct 2016)

I reckon it depends. I've doubled my phosphate dosage in my macro mix to combat gsa and it still appears. I just scrape it away before it gets to hard.

Also for the lights, have you considered using a plug timer? You'll never have to think about turning the lights on and off ever again and it will be consistent.


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## kadoxu (28 Oct 2016)

Courtneybst said:


> Also for the lights, have you considered using a plug timer? You'll never have to think about turning the lights on and off ever again and it will be consistent.


I have, but it wouldn't work with the cheap lights I have. I would have to buy new proper lights.

The lights are touch activated and have 4 modes. 1 - Off, 2 - Blue, 3 - Blue & Red & White, 4 - Red & White. They change modes whenever I plug them off and on again until it reaches the "Off" mode... after that I need to turn them on by touch.


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## Manisha (28 Oct 2016)

A timer is great, however with my aqua one stock light it always reverts to the blue moonlight setting, grr.... so have to manually switch to proper lights anyway! annoying! When are you due btw? can't be long nows ☺☺☺


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## rebel (29 Oct 2016)

It can depend. You can easily double the phosphates and wait. But it doesn't always work. Reducing light almost always will work. 

I hear you can get GSA eating nerite snails over there.


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## kadoxu (29 Oct 2016)

Manisha said:


> When are you due btw? can't be long nows ☺☺☺


It's on late February. I still have a few months to sleep! 



rebel said:


> I hear you can get GSA eating nerite snails over there.


I have 2 already...


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## EdwinK (30 Oct 2016)

Neritina natalensis can consume a lot of the plant's surface alongside with GSA.


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