I think I remember seeing someplace that starfish are very sensitive to salinity changes. Is there a safe-zone of salinity change for fish and corals that would be lethal to the star fish? I also have hermit crabs in the tank.
I could take out the fish and corals. I would first take out all the live rock to get the fish out, then put the live rock back in the tank and do the salinity drop. If I visually inpect my corals (montipora, the acro, and others that I can easily inspect) and pick off all sea stars, is it possible that there would be larvae that are invisible that would still be on them? If so, then how possible?
I'd then add salt to bring back the salinity to original levels.
If I take everything out but the live rock, would a change from 1.026 down to 1.020 be enough? or more to 1.017?
After I get input from this, then I'll try to figure out the best way to raise the salinity.