I am trying to lower my pH. It is about 8.6 right now. I have been using regular tap water, but just recently started using RO. I have a mix of small fish and a few corals (sm-med). I am running 48" PowerCompacts from Custom Sea Life on a 80gal. I have a Prizm protein skimmer and an Emperor 400, and a bunch of live rock for filtration. I live in an area where the limestone deposit is high. I heard about regular water changes and maybe some kalwasser mix?? Any suggestions?