Good Morning Jay,Regarding the specific gravity, 1.026 is normal seawater, about 35 ppt salinity. HOWEVER - many LFS maintain their fish in low salinity systems. If you try to acclimate one of these wrasse from, say, 1.020 to 1.026 in one shot, there will be issues. You can always drop the salinity of a fish easily, but raising it that much must be done in stages, I take 3 days for that. That said, DD probably ships at a higher salinity, can you confirm?
I don't see anything externally on your wrasse, but I've seen half a dozen similar cases (including one that I had) where they swam oddly, disorientated, but most of them would still eat o.k. I have no idea what causes that, sorry.
Jay
How fast does osmotic shock present in a fish if the salinity was very different?