I NEVER try to adjust the ph of my tank. The ph in my big tank is a little bit different than my others due to the two huge pieces of wood in the tank, but that is fairly constant since I have a constant water changer on it. IMO you're asking for ph fluctuation if you try and control it.
I have dropped shipped pbass 2-4" after no more than 10 minutes of acclimation due to how their water looked. I didn't check the ph of the bag, but it must have been different at least a little bit.
If I was getting new orinos in I would leave the ph in the tank alone and drip acclimate (or some form of that - I normally do it with a small glass and just add a little bit of water every 10 minutes or so) for 30 minutes or so depending on the condition of the water in the bag when I get it.