I have a 100 gallon saltwater tank that has been set up and working for a little over a month now. I have a wet/dry filter with a protein skimmer, live rock and live sand, a humu humu trigger fish, a dog face puffer, 2 blue damsels and a maroon clownfish. For some reason my specific gravity keeps going to 1.029 and 1.030. The ammonia level is 0, Nitrate and Nitrites are good, PH is 7.8. I have done a 5% water change with distilled water and R/O water and after a few days the salinity goes back up to 1.029. What other ways of lowering the SG can be done? I need to do a water change but am fearful by adding the salt it will continue to rise. Any suggestions on what to do with the SG? Also any suggestions on raising the ph level? I have previously added PH Buffer and PH level still sits at 7.8. This is new to me and need advise quickly so I can make sure I don't lose the fish I have.