I hope you were successful in your GSA treatment! I am finally deciding to tackle mine and have reduced my lighting which helped with other algae but not GSA.
What deets do you use? I have root tabs but my nitrates will rarely rise above 5ppm even with sparse water changes, I expect probably in thanks to the algae farm. I've heard adding phosphorus can help so that's next on my list.
All the best 🙂