ph of freshwater aquarium

Question
Hi.  I am currently switching my coldwater tank to a warm water tank.  No fish in yet.  I got the ammonia and nitrates down, but am struggling with ph.  The water from my well tests acid (my tank water was usually acid when I had my goldfish)  So I tried raising the ph by adding some baking soda.  Now the tank ph is quite alkaline.  I've done several water changes with my acid well water, (with gravel vaccum) and afterward the tank tests neutral initially, but then 24 hours later, it changes back to alkaline again.  Help!  Should I empty the tank and start all over?  Someone suggested to use distilled water because well water ph can be unreliable.  I'd rather stick with my well water if possible.  Thank you for any suggestions.

Answer
Well water tends to read high on the pH scale... Once you get the tank established the pH will drop naturally as the body of tank water ages... it will fluctuate as you add in new water but will revert back to a lower reading as it settles.  What is the pH of your well water? What is the pH of your tank?  and what is the pH of the old tank water?   dave