It shouldn't be enough to change your pH to drastically...but I would still add it slowly over a period of time. Mostly because all that sand flying around isn't what you would want to breathe, right? As stated above, get yourself some nice aragonite sand. Here is a link to where I just got mine, pretty good deal if you have trouble getting specific things in your area.
Aragamax Aquarium Sand
They have other kinds that might trip your trigger, so search around. Infact, now I wish I had so I could have black or pink sand...lol