Hello! I have a 30g tank, about 4 years old, with soft corals, a couple of clownfish and a goby. Have never been able to keep any LPS corals or zoas. The soft corals like Kenya tree, leathers seem to be doing ok. Mushrooms arent thriving. Decided to check alkalinity, Ca, Mg today with the Salifert kit and got 5.0, 470 ppm and 1170 ppm. Planning to do a water change tomorrow (about 3 weeks after the last one). Could you please advise on best way to get the dKH up? I use Instant Ocean Reef Crystals. Thanks in advance for your help.