Ppfd and dli are definitely great tools, but the problem is getting accurate readings, even with the photone app. And an Apogee meter is $500. I used the app and set DLI for what was recommended for my new hlg 350r, and my buds foxtailed pretty badly, so be careful using that exclusively.
Hey welcome to the community, it a great place. So others above are spot on, plus you already have photone app, sounds like your ahead of the game. My 2 cents your right 20. to 40 a big jump on one day but I wanted stress to much about it. Maybe lower your DLI to 30 and increase it slowly over a few days. But plants look good a full photo of entire plant would help out.
I know is not 100% accurate, but i saw a PAR test on YouTube for fc 6500, and set the lamp to the power/height that should be okay.
I have now rise the lamp to 65cm and decreased power a little, i hope it helps
Plants is only about 20-25c in height, is this a problem or sign of stuned growth?
No they look good for 30 days, only on 2nd grow myself and I was always thinking mine where this and that but all that matters is in product. But all have good color and you have plenty of light so keep up good work, and keep us informed. Best of luck and happy growing
Looks good. I ran into trouble in late flower with my new light. DLI showed in the correct range, but plants foxtailed. In fairness it was a 70/30 sativa (pure power plant), so maybe genetics played a part. Starting an OG kush now, so we’ll see.