Generally speaking, 7.5g is the upper limit for 4oz of the
transport matrix (and, obviously, 15g for 8oz, like in the original Avant gels). Well, nobody really knows the TRUE limit, but 7.5g is pretty close.
We usually recommend 7g so you err on the side of caution and don't risk losing absorption by possibly oversaturating the solution; it's easier to mess up 7.5g if you're .5g over than it would be to mess up 7g if you're .5g over.
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