Balls to the Wall, dang! I may have 4 males in my 4x4, I'm understanding your tears. going into day 9 of flower and no flowers yet, I'll check at 7 for maybe the last time.
Bump. Any updates? Im fighting a similar issue.
Discarded nutrition ppm, ph of water, lights.
Now I´m thinking offgassing of some sort. Just removed a PVC curtaing that was covering the air intake for the grow door room.
And added CO2 bag. lost 12 FB seeds already.