how big is your tank there are several easy ways to raise it , is your tank covered or not
also consider this ph is lower in AM and higher around 6pm in eve from lights being on
circulation is another factor
the safest way to raise ph it can be done using seltzer water be sure it's the pure type not the ones with sugars and other stuff , I used 9 1/2 gal
bottles in my 90 when I first set up 2 years ago , I use small amounts of baking soda as a buffer to keep stable,
another way you can raise ph is baking soda just add it slowly as it wont give a correct reading until it circulates at least 8 hrs.