CVG and Coir have the same opportunity to contam, both substrates need to be pasteurized before use.

C= Coir V= Vermiculite G= Gypsum

Verm and Gypsum are not nutrients. They are used in conjunction with the coir to help retain moisture.

I have used both Coir and CVG and i have seen better moisture retention and less cake dry out with the CVG especially with second and third flushes.

Vermiculite and Gypsum are really cheap when buying gardening amounts if you wanted to add that to your grows.

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If proper pasteurization techniques are used there is really no higher contam rates in my experience.

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I find the Verm helps with the consistency of the cake then just coir alone. Gypsum helps with clumping in the grain spawn process I’ve read.

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There are tons of people on either side of the fence on this one.