Can the KNO3 and KH2PO4 be mixed together for E.I. Dosing??

rs18alpha

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Feb 3, 2017
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When I start to use the E I method I was wondering if I should mix the KNO3 and KH2PO4 together?
I would think it would be better to keep them separate if I need to make fine adjustments.

What do you think?
 

Phishless

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I mix a standard EI macro mix 500ml.
Also a bottle of each = to Flourish N &P 250ml.
If I need to go light on PO4 I dose less EI mix and add a splash of N.

But it's all up to you!

I am guilty of testing water about every ten days for N & P
 

slipfinger

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You can mix all macros in one dosing bottle if you like or you can mix them individually, totally up to you.

When I dosed macros as solutions (I dry dose now) I mixed enough to last only a couple weeks. This way if I decided to change dosing I was not wasting.
 

rs18alpha

Subscriber
Feb 3, 2017
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Pennsylvania
I mix a standard EI macro mix 500ml.
Also a bottle of each = to Flourish N &P 250ml.
If I need to go light on PO4 I dose less EI mix and add a splash of N.

But it's all up to you!

I am guilty of testing water about every ten days for N & P
Thanks, once you understand this stuff it makes sense finally!!

One more question: I have an old batch of Mac mix in a 500mil bottle that I was using when I was dosing the PPS PRO method. I know I can add more N and PO4 to reach the proper dosing amounts to reach the correct ppm. But in this mix I also have K2SO4 and MgSO4
There's 29 grams K2SO4 -20 grams of MgSO4
I'm dosing 15mil at a time so that would be 2.6ppm K and 0.3944ppm Mg I don't know if my tap water is low in magnesium as far as the MgSO4 goes so I don't know if that would be a problem? And the extra K I see that some people add extra any way.
So, in conclusion would it be ok to use the old batch?
 

burr740

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Old batch should be fine as long as its still clean and clear looking. That's not enough Mg to make much difference either way