PPM Question

[Frank White]

I just want to see if I have a decent grasp on PPM...Please let me know if any of the following is incorrect...

Checking PPM over time gives an indication of plant intake of water versus plant intake of nutrients. If your PPM goes DOWN over time, your plants are taking in more nutrients than water. If your PPM goes UP over time, your plants are taking in more water than nutrients. You are basically looking for homeostasis or equilibrium with respect to water intake versus nutrient intake. And of course, PPM can safely rise to higher levels the bigger the plant gets.

Let me know where Im going wrong in my understanding....

 

[LowRider]

just going to give this a friendly bump cause i'm wanting to know this also. :bump: :bump:

 

[King Bud]

Right on.

It's practically essential to keep a time table of your readings, so you can check back and figure this kind of stuff out.

..now.. can someone explain pH drift as simply? I know I can't.
not that it's really necessary to understand it.. just keep it within the acceptable range and pH is no problem..

found an article you might enjoy, while trying to answer my own question: hXXp://www.flairform.com.au/hints/dosing_procedures_hydroponic_nutrients.htm

edit::baby: man, the more I read, the more I realize how little I know.. time to start reading through my books again

 

[Frank White]

Thank you very much. I was starting to think people thought I was an idiot. So many thread views, so few responses. I was getting worried. Thanks for the bump and thanks for the confirm.

 

[King Bud]

You're very welcome.

I'm afraid my answer is extremely limited though.

There's just so much to keep in mind. For example, PPM (or EC, or TDS) can rise, because not all of the nutrients are being absorbed by the plant. Over time, your reservoir will have a stockpile of 'excess' nutrients, that will just never be absorbed. Does that make sense?

I'm sure there's other stuff I'm not aware of, that can affect readings.

This stuff can get very complicated when you get too detailed :hairpull: it helps to have an understanding of chemistry (moles, and acids, etc)

There are others here that seem to truly understand this hydroponic business.

I'm sort of hoping someone swings by, and mentions the trick for when it's recommended to change reservoirs.. it's something like when your PPM starts to rise, and your pH starts to lower.. or is it the other way around

Bah! Every few weeks does the trick.

man I'm too tired, I better not spew too much possibly false information :laugh:

I hope you're enjoying playing, and learning about this stuff.. I know I am (despite it being with other plants).

Trust me, no one important thinks you're an idiot.