Aquasoil Kh Buffers

I am planning to build my first planted tank with aquasoil (most probably with tropica, since thats the one I found in my near fish shops). Currently all my planted tanks are with inert gravel & root tabs, and I add Saltyshrimp GH/KH+ to my RO water. Should I buy only the GH additive to keep the soil buffers and when the aquasoil buffering stops I switch to the GH/KH keeping in mind to add kh slowly because of the livestock, or should I start with the GH/KH and have control of the parameters from the beginning, since I will exhause the buffers quickly. This tank will be in my living room and don't wish to change soils every couple of years, and I seen tanks on internet one is tom bars that has been running for over 8 years with the same soil.