I have been wondering this myself so I hope someone answers you. I dose EI ferts once a week (third the recommendation because I have low light/no C02). I add root tabs once a month for some of the plants that seem to need it- particularly my biggest crypts and aponogetons.My tank is getting to be more stable, but I've noticed that the day after I do root tabs I always have higher nitrates and an outbreak of fine thread algae almost like sparse pale fur on some leaf surfaces. Even if I dose less on the dry ferts the day of doing root tabs, I get this.
I think next month I will try a blackout day and see if it helps.
I think next month I will try a blackout day and see if it helps.