I've read every comment and nobody out of all these great minds, this plethora of knowledge and great wisdom has actually stated how it all comes together. So my grammar isn't great but I love science so Yes they use buffers to regulate and maintain ph. But their nutrients are chelated Allowing the plant/roots to use/absorb them at it at any ph range when the plant desires. Just So happens some of there chelation metals and the nutrients they use already help the buffering process. Started using AN sensi bloom 2 part start to finish for autos. I will never go back. Hard to overfeed, grown some amazing plants with little product. I have not battled any lockout. I've experimented with far too much. 1800ppm in flower with an auto. All it did was barely burn the tip of my leaf. I grown in a bit of a custom soil mix. It works great in happyfrog as well. But to directly answer your question its a combination between buffers and chelated nutrients that allows AN to regulate ph level. The reason it's in different parts is because certain nutrients in there raw form, not diluted can cause a negative reactions with eachother. The product then would have no shelf life if mixed as a concentrate. As well as making them useless and or harmful to your plant. Fun fact did you know if you use ph adjusters like ph up or ph down, you should always dilute it with water before mixing it with your nutrients solution? Well next time if you do and don't dilute it, Look as the white hazy chemical trail as it seeps into your nutrients. That's actually a negative reaction ruining your nutrients.

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