I have 45g aquarium, 2 clown, 4 fire fish, blue sapphire damsel and 2 chromis. Altough damsel was last to introduce it has become very dominant and a bully, it particularly chases my chromis during feeding and also very agressive towards my pink turkey baster and plastic clear toothbrush.
It has started to intimidate my clowns which are much bigger so I will be removing and trading in.
It's a beautiful coloured fish, very dark when calm but tends to get lighter when agressive but for me, to keep peace it has to go.
Just a thought on my experience in last 4-5months of adding chromis with blue sapphire damsel :)