I would suggest mixing up a bucn of salt water ahead. Then place all rock that was removed into a plastic tub, siphon water out of tank to fill tub (cover rocks, replace water in display tank with new salt mix. Now geta powerhead moving water in the tub, leave it one week and then just rplace it into your tank. Now with a scuplted new rockwork display, change all filter material, clean your skimmer, clean your viewing panels, (it's like a brand new set up). Now don't touch it for a week accept for topping off. Then test your levels. If anything is off then do a water change. Once NH3, NO2, NO3, are all zero then start worry about pH, Alk, abd Ca. Go into the archives and print off a chart by Reefnut on Alk and Ca levels. Try to main a 1.023 / 1.024 SG, pH 8.3 / 8.4, Calcium in the 440 - 460 range and Alk in the 180 - 200 ppm CaCO3 range. Good luck