Indoor How does a ppm meter work?

[aceboogie]

so why is that its more important for hydro then it is for soil? sorry for the stupid questions.

 

[Muddy]

Even using the AN pH Perfect I record my base pH and PPM, then the pH and PPM after adding the nutes. I then feed and see how the plants react. This has given me some general guidelines on how much I need to feed. So far it seems that most of the strains I've grown can take up to about 500 PPM without showing signs of overfeeding. That's not to say that will hold true on another, more sensitive strain.

 

[aceboogie]

thanks again muddy, youve been very helpful.