[TurboSnail8898]

Dude, find a new LFS, the one you are going to apparently has no idea what they're talking about. pH should remain stable and within range of natural seawater if your alkalinity/calcium are maintained at appropriate levels. If you don't have coral then regular water changes should replace the calcium that is used by coralline growth. Most people don't use air in their reef tanks because it can cause increased algae growth, at least thats what I've heard.