would a SINGLE chromis be fine in a 40 gallon with 1-2 clownfish, 1 orchid dottyback, 1 midas blenny, 1 banggaii cardinal, 1-2 fairy wrasses, and 1 yellow coris wrasse? (will be no more than 7 fish in the end including this single chromis). I've heard horrible stories with chromis in a group where one kills the rest, but would 1 single chromis be ok? or would it be aggressive?