Is This PH issue?

[Dbdigger]

Hello All, I have investigated the Plant Problem pages. We have a brand new PH pen and its calibrated. Our lights are at 75% power. Distance is more than 36” away. We have been going light on nutes. It is week 2 of flower. PH has been reading out at 6.2 consistently. Today we watered & PH in was 6.8, PH out was 5.9.
in your opinion are these brown spots PH issue? Plant is veright colored since flipping to flower

 

[PLreef]

To me it looks like she's asking for some Cal/mag and food in general.

https://www.growweedeasy.com/cannabis-plant-problems/calcium-deficiency

https://www.growweedeasy.com/cannabis-plant-problems/nitrogen-deficiency

 

[homegrown]

Yes i would say it is..if your water in is 6.8 and drainage is 5.9 you have issues. I grow in coco and i find my happy place around 6.2 drainage. Not sure about FF(if its actually soil) but if it is, your run-off should be higher still

 

[Rwise]

I agree, you have PH issues.
https://www.growweedeasy.com/cannabis-nutrient-deficiencies-ph-picture-guide

 

[dilvish]

when the plant pales like it is there is a nitrogen deficiency. In soil calmag is optional but some plants need it more than others. It does look a bit like a magnesium deficiency and it's likely because the PH is off. Try recalibrating the PH tester before doing anything else. Although manufacturers say it's calibrated right out of the box, chances are it isn't so it's a good idea to make sure before using it. many of the cheaper ones (under$25) usually need to be calibrated every month or so IMHO.

 

[Dbdigger]

We did have to calibrate it right out of the box. I tested it today in the 7.0 solution and the ph tester said 7.1. We ended up doing a flush today, and actually used our tap water. We have a RO machine that we use for drinking and for the plants. We've concluded that it also is the Ocean Forrest is not holding the nutrients in the soil very long at all. We've had this problem throughout the grow once they get flipped to flower. These two wedding cakes were in veg longer. . Almost identical issues.

 

[dilvish]

most "hot" soils use up their nutrients in about 4 weeks. Going "lite" on nutrients is not recommended unless there is a significant problem. In your case it looks like they are just starving for nitrogen because the soil nitrogen was used up when you flipped to flower. If the PH tester is relatively accurate then it's not a PH issue unless you are outside the soil range (6.5 -7.0). Give the plants a good flush with properly PH'd water and then give them the recommended dose of nutrients going forward.

 

[dilvish]

Additionally the light is at 75% but at 36 inches from the top of the canopy? I'd recommend you crank it to 100% OR move it to about 26 inches from the top of the canopy.