Rockwool runoff

I am dabbling a little in rockwool. I’m checking my runoff for ec and ph.
I’m putting in 1.6 ec and getting a runoff of around 0.9-1.2 ec depending on plant.
My ph that I’m putting in is at 5.9. My runoff for ph is ranging from 6.5-6.9 depending on plant.
Is there something I’m doing wrong? Isn’t the runoff for ph supposed to be the same as what’s going in?
I understand if the ec runoff drops, that means that the plant is eating.
Anybody wanna shed some knowledge please

you must increase you feed even if 1.6 sound already high

pH should rise when the plants are feeding.. If it's dropping, your ec is too high.

yeah moderatly .. seems the runoff is significantly lower than the feed
personnaly i try to have my ec feed= ec runoff .. with a ph a bit higher in the runoff yep

Try a lower pH to allow for drift.

Your runoff will naturally be a higher pH. As the plant uptakes certain nutrients the pH of the root area goes up.

Could you mention
1) the age of the plants
2) the stage of the plants
3)the size of the Rockwool cubes
4) how much liquid are you using
5) did you presoak the Rockwool in an acidic solution first?

When you put in ec 1.6 solution, and get out 1.2, this means you have not completely exchanged all the liquid in the media. The plants don’t instantly take up nutrients as you pump them. There is a difference in the input and output. So this means as well that the pH of the water should have a difference as well. If you used more input water at 5.8pH the runoff should come out lower.
But it is normal to have the high pH runoff. Unless you didn’t presoak the Rockwool, then you could have such a basic media that it buffers the pH naturally higher.

If you are in Veg then things are normal. If you are in flower, the pH rise shouldn’t be as great. Let us know

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