That chart just shows the optimum ph for the uptake of different nutrient elements for a plant...If you fall too far out of range it will be harder to uptake certain elements...

In flower I drop from 5.8 to 5.4 in the 4th week, then 5.5 in the 5th week followed by 5.6 in the 6th week followed by 5.7 in week 7

Some growers find that their ph raises a little throughout the week, so they start low...i.e.5.4ph, and let the ph swing upward to 5.8-6.0ph by the end of the week.

You can run your hydro nutes from 5.4 to 6.0ph with no problems, and most of the time if you are staying in that range then you won't see anything more than a slight deficiency from time to time at worst. peace
latewood Reviewed by latewood on . Please help me understand the FAQ charts So, if I understand the FAQ chart correctly, I have not been letting my plants get any Phosphorus or Manganes because my PH is below 5.8. How is this possible? Wouldn't my plants be dead or extremely sleepy? I thought they needed that stuff. Am I reading the chart wrong? Also, I thought I remember posts about people keeping their PPM below 3000, but the charts say not to go above 1400. Is this what you guys do? Will they fry above 1400? Oh yeah, I'm growing in hydro. Rating: 5