how much PO4
The only issue I have in my tank, is some GSA on plants leaves.
in my 300ltr planted tank I inject CO2 from PH 7.43 to PH 6.10.
My lights are medium 4 T5×39W.
I use EI and do weekly 50% water change.
I know to avoid the GSA, I must set higher the CO2. I already did this for a while as I drop the Ph around 1.3
Also I add more and more PO4 to eliminate the GSA. These days i add 5.4 ppm weekly.
The day before water change i have 2ppm of PO4, and the next day 0.5 ppm of PO4.
So can i go higher by adding more PO4 or is dangerous???