Lance's 225 gal tank

[Lance]

Does a dark blue/purple Cali Tort turn green before bleaching? This coral has been losing colour since the middle of last month. Turning from blue to darkish green and now to a lighter, bright green colour. I've been moving it around the tank: less light; more light; less flow; more flow; but nothing seems to help. I've aready lost one SPS colony and several others are not doing well either.