pH problem!

The tank cycling shouldn't have a huge effect on your pH.

 

like how much would it change it? .1?

 

during cycling there is amonia ect as it cycle,s it may decrease your alk level it does for me every time i set up a new tank ph will drop . but addiing air like a skimmer would also be a good idea. it's better to change a small amount of water than to keep adding buffer you could boost the alk, to high

if the power head has a return nozzle have it pointed upward to keep the top of the water moving ,, rippling. that will help in the gas exchange and let the c02 excape.