Guppies PH

the pH coming out of your tap is the pH you should have in your tank. don't mess about with your water chemistry or you'll create an instability which will result in a multitude of problems.
 
Also, if you go to a LFS, there water will most likely have the same ph as your's, so they will already be used to the ph. As long as you acclimate the fish properly, and keep the ph stable, the guppies should be fine.
 
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