I wouldnt bother doing another test, just dose 5ppm no3 and it will bring it between 10-15ppm in the tank, let it drop back from 15ppm and then in a couple of days you can test and just add what ever amount of ml to bring it back to 15ppm, let it flucuate between 10-15ppm you dont have to be exact.
Just keep dosing and keep the co2 in check and hopefully the algae will slow down or stop growing, keep removeing as much as you can.
Just keep dosing and keep the co2 in check and hopefully the algae will slow down or stop growing, keep removeing as much as you can.