Home Forums Q&A Light stress ! Reply To: Light stress !

Points: 961

@WetDawg1967, sorry for the late responce. In the picture of your girls, first thing is they look very healthy. I do see what could be just lighting or could be the beginning of a Mag (magnesium) deficiency. When the leaf veins are dark green and in between the leaf is yellowing, it’s a mag def, and LED’s are notorious for causing mag (and other) def. Are your leaves starting to look like that or was it just the lighting? Google “magnesium deficiency marijuana leaves” for some pictures, oh and here is a link to a video on the subject, https://youtu.be/SjEQivmJ03A

As for how close you can run your SE7000. The simplist answer I can give you is I can’t say with just the info you have given. If I make the assumption you are not using CO2, then a good answer is at least 600 micromoles (umoles) and not over 1000 umoles. If you are using CO2, then according to Dr Bugbee, there isn’t really any ceiling, AS LONG AS YOU INCREASE ALL OTHER INPUTS, water and nutes! So the next question is how to measure umoles? Well, truthfully you need a ‘true’ PAR meter. The gold standard meter IS Dr. Bugbee’s Apogee meters, here, https://www.apogeeinstruments.com/ , But if you don’t have NASA funding ($500+), there are cheaper options. Here is my thread on the PPFD maps I made with a product Shane from Migro recomended.
Here are links to my threads on this. My new PPFD light meter setup, https://forum.spider-farmer.com/forums/topic/a-never-ending-thread-of-user-made-ppfd-maps/
and a link to De. Bugbee’s interview with Shane from Migro, https://forum.spider-farmer.com/forums/topic/latest-dr-bugbee-interview-from-shane-migro-a-must-watch/ Pay close attention to what the Dr says around 45 minutes in about PAR and C02 maximums.

Keep growing and hoping that info helps with your girls.

New Report