help fish start dying

[mohammadali]

HI
I check my water at the store they said everything is fine just a water change will be good i did 10% water change all coral closing and same to anemone but my 3 fish died right after 3 hours water change
salinity 1.024
PH 84
temp 78

here is the video after 3 hours water change
http://www.youtube.com/watch?v=wtkLVSzQuvk