Reeferntraining / jjoos99 thanks for your replies. As you mention jjoos99 my substrate does get a "crust like build up" on it - great to mention, it cleans up ok just looks weird. I am in the process of lowering my Alk as well, currently in the 9.3 - 10 range and I have dialed back my Mag as well.
Thanks for the insights, always a help!