Need help understand pH, PPM, EC in Coco

My head hurts from reading so much about pH, PPM and EC. Could someone PLEASE help me understand. I realize there are variables but looking for a basic explanation of how things “should be”. Started grow in Coco only and using RO water and organic nutrients. But going forward don’t know how to interpret the “numbers” and would prefer NOT to wait until plants are exhibiting signs of deficiency or burn, etc.
Range for pH in and out - in veg & flower
Range for pH runoff - what is the goal I read within 0.5 of what went in but is that right?
Should PPM out be the same as PPM in - if not what is goal?
Should I measure both EC and PPM or pick one?
Thank You!

Organic nutrients won't read properly on a PPM/EC pen as they read mineral salts dissolved in water only. PPM/EC pens read the same thing, TDS or Totally Dissolved Solids, but display the results using different scales. Kind of like -40C and -40F are exactly the same but the numbers don't meet up anywhere else on their readings.

Luckily EC and PPM are directly related. Most pens use the 0.5 or Hanna scale unless they are displayed as EC. Find that out for whatever pen you use or are going to buy. Should be info at their website or online somewhere. This pic is the right size to print out for easy reference.



I never use coco so can't help you there. I grow in ProMix HP mostly or do DWC.

I use pH Perfect nutes with RO water so never check pH either in or out.

Good luck!

Been there. Only wish I had the site below to learn from when I first started with Coco.
(If I tried to explain this stuff.....both of our heads would hurt! lol Seriously, hope this is of some help.)
https://cocoforcannabis.com/how-to-prepare-and-buffer-coco-coir/
https://cocoforcannabis.com/

You got this!