2" is probably good. From the pictures it looked like less than 1". Goes to show pictures are sometimes hard to judge by for rock and sand.
Okay so bloom was after the anthias. Then my educated guess was the anthias brought in a disease or parasite and the algae bloom combined pulled some o2 out of the environment causing some stress. The fish then spiraled as we say. More stress, more disease, deaths (also causing water changes with deaths).
QT would probably have saved the system from the disease, but a few fish still may have struggled with the bloom depending on if the o2 was low.
Glad you are getting a qt set up and also for the wrasse. Good bucket of sand in qt for the wrasse and some meds and hopefully he/she pulls through and you can begin with fish again in a few months.