Had high NO3 in Sept.Salifert told me zero.
But hair algae grow all over the tank.
Finally got a reefer to help confirm my NO3 reading.
It read 25 ppm.
Do daily water change but don't do much help.
Do weekly algae pucking.
Still the same.
Last week got Bio Pellet from a nice reefer.
Hope it help.
Will take the NO3 reading this few day and see how