You can lower it if you want, using muriatic (please read the link in my sig before handling it) or dry acid. However, if your fill water is high in pH, then it's going to rise again anytime you top off the pool, so you may or may not decide it's worth it. I would test your fill water and see. My fill water is pH 7.8, and no matter what I do to try to lower it, my pool settles at that level, so I finally just quit trying to chase the number and let it be. You might find yourself in the same predicament.

Janet