quick soil ph question?

hi guys
have been growing a while but not as experienced as some of you guys and have a quick question about soil ph, i grow indoors with all mix and the full bio bizz range. i keep seeing it where people are giving advise to people and saying why are you phing the water and checking the soil when your doing organic grow.
i thought any indoor grow had the keep the ph in check, or have i lost the plot and totally getting the wrong end of the stick. i always thought the plants could make the soil acidic with salts and what not.
can someone clarify whether or not organic grows need water to be set to a ph of 6.5. or is organic soil magic and it doesnt need doing.
thanks for any advice.
lu

its grand i kind of found the answer, nothing straight forward though. lots of differing opinions. some yes some no, but theres also lots of factors to be taken into account.
lu

Every grower should monitor their pH's. Even different bottled waters can have different pH values and tap waters can vary even more. Some of the best fertilizers have pH's that are dangerous to the plants and need to be adjusted. Even if everything you give the plants is the perfect pH, the substrate's pH can slowly change over time because of things like microorganisms and slow chemical reactions.

Some people use recipes that other growers already designed to have the correct pH while others simply get lucky and have no pH problems during their grow. Still others have pH problems and just don't know it. It's possible to get by without testing pH but if you grow for long enough, you'll eventually have at least a mild issue because of it, even if you don't realize it.