I would not add anything that you are not testing for at all.. Adding Epsom salt is in ways bad for your tank but in essence all that adding Epsom Salts is doing is boosting your Mg
which your salt should already have NSW
values to it.. So I would not recommend doing it even if your Mg
was low.. I would use a good quality additive in that case.. The only way that I have been know to safely promote coralline is by turning off the skimmer and scrapping some off the rock.. Other than that good Ca
levels are also needed to grow coralline which if you are doing regular water changes you should be pretty ok with that.. If you are planning on getting into corals I would suggest you at least get a Salifert Ca
test kits.. Seachem is also good but not as.. One of the Sponsors of the site should be able to get you some of them...