During the growing phase a plant needs and will take in equal amounts of anions and cations.

To take in a negative ion a plant has to release an electron (⁻). This electron when released into water is negative load creating a hydroxide (OH⁻) particle. This OH⁻ particle will bring the pH up in the root zone/substrate.
The anion mainly responsible for this  reaction is NO−3.

To take in a positive ion a plant has to release a proton (⁺). This proton when released into water will add a positive load creating a H⁺ particle. This H⁺ particle will bring the pH down in the root zone/substrate.  The cations mainly responsible for this reaction are Calcium (Ca²⁺) and Magnesium (Mg²⁺).

When your using SNOOP’S PREMIUM GROW a plants uptake of the negative and positive ions in the grow phase are balanced. This regulates the internal pH of the substrate as well as the pH levels you choose to feed with from your feed tank and thus keeping the pH in a range which allows the elements to be taken by the plant.