# K2so4



## Jesse2504 (Jun 3, 2009)

I just bought some potassium sulfate for my aquarium plants, will this provide much benefit as most guides say to use potassium phosphate.


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## Seattle_Aquarist (Mar 7, 2008)

Hi Jesse2504,

Actually both are used in planted tanks, one as a source of potassium and one as a source of phosphate.


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## Jesse2504 (Jun 3, 2009)

Ahh thank you, I am also looking into getting:

PMDD Pre-Mix 1 lb contains 1 part each of Potassium Nitrate, Potassium Sulfate, Magnesium Sulfate, Plantex CSM+B.

How would I work out dosing when they are all in equal parts since not all of those elements are dosed linearly compared to each other and since its mixed I cannot divide them. BTW I can only get the premixed packs since its against the law here to have KNO3 by itself in large quantities.


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## Seattle_Aquarist (Mar 7, 2008)

Hi Jesse2504,

One of GSAS members, Erik Olson, has operated "The Krib" website forever. It was one of the earliest aquarium websites. Here is a post from 1997 about PMDD that I have read in the past. Some of the supplier information may no longer be current but the dosing information you asked about is there.
http://www.thekrib.com/Plants/Fertilizer/pmdd-tim.html


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## imeridian (Jan 17, 2007)

Jesse2504, if you intend to use a modern dosing system then you'll need KH2PO4 or equivalent source of phosphate. K2SO4 cannot be substituted for it in that regard. You also cannot mix KH2PO4 into that premix as the CSM+B contains iron. It might be fine if you keep it dry, but as a solution you'll have undesirable elemental bonding. If at all possible try to find another alternative method of staying legal, perhaps they'll mix together macros without the micros for you.


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