I agree with Picavores, whenever you see blue water in a LFSs tanks, it means that tank is probably being treated for something, so don't buy anything from that tank.
Blue water often means treatment for ick, but.....many people use ick treatment for any random malady, which isn't always the right thing to do.
I suggest you start going to, and or join the Capital Cichlid Assn.
Capital Cichlid Associationhttps://www.capitalcichlids.org/forums/
There are very knowledgable members who can help you with everything from water issues to fish selection.
You can also get very good quality fish at their meetings and auctions, instead of at questionable LFSs.