Here it is some data of the water analisis:
PH: 6.6
CO3CA 266
Phosphates 1,8 mg/l
S 0.95 mg/l
Disolved O2 7.2 ppm
DBO 122
CACO3 203 mg/l
NO3- <5
NO2- 0.01
SO4= 103 mg/l

Now Im planning to use Aluminium sulphate to deny P to the algae. What do you think about it, can you tell me how do I calculate the amount of alumiun sulphate I need?
I have done tests on bottles: the water turns milky, and a cludy water forms.


I know that in a long term , to control phosphates I should have acuitic plants? Im in that way, but for the moment I need to control this algae bloom.
Thanks for the help and advices