MY corals started looking similar.
I'd gotten lazy and started using a hydrometer instead of a refractometer.
Hydrometer was reading 1.25 but when I calibrated and checked because I couldn't figure out why my coral (especially my chalices) were looking so bad all of a sudden and some Algea was really starting to flourish.
The calibrated refractometer read near.y 1.3.
Have been slowly dropping salinity since but my corals were looking pretty similar to yours.
Still concerned about long term effects.
My fish, euhpyllia, zoas and shrooms did not seem to mind at all.