I just searched for one of my old posts from last year. I was experimenting some with the OTO test kit, as I had to maintain extremely high FC last summer due to astronomical CYA and water restrictions
"When it's yellow yellow yellow it's roughly 10. At 12-13, roughly, the color will be school bus yellow (maybe Caterpillar - construction equipment, not bug - yellow). Hunter orange is around 18."
"When it's yellow yellow yellow it's roughly 10. At 12-13, roughly, the color will be school bus yellow (maybe Caterpillar - construction equipment, not bug - yellow). Hunter orange is around 18."