i would add a two part solution for calcium/alkalinity. i have had success with Kent Marine NanoReef A and B in some of my small tanks. it also will provide some trace minerals
i agree. the bacteria in your tank are going to need some time to get to populations high enough to clean the water well, you will also get a lot of algae in stages early because of the dirty water, aka cycling. this process takes a few months
because you have put corals in your tank early you are going to have to work a lil harder if you want to keep them healthy, not that they will definitely die if you are lazy but if you do a water change a week for the first four or so weeks your tank will be much happier, then taper them off until three months only do one a month or so. mushrooms are hardy anyway
good luck