Hmm... in looking it over, for $25 I can pick up the whole pack of 1lb each of KNO3, KH2P04, K2SO4, CaNO3, MgSO4 & trace. I figure if I get both the Ca and the Mg I can make my own GH booster.
I figure I will mix the K2SO4, CaNO3 & MgSO4 at a certain ratio to make sure the GH and mineral content is good. I am posting elsewhere on how to mix it

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