Juvenile blue angel fish are very common in Qatari water. While navigating to find the diving spot many time, once I see the blue angel fish I know that I am close by the dive plateau as they like to live around natural or artificial reef.  
The Arabian angelfish grows to a maximum length of 40 centimetres (16 inches). The adult is generally dark greyish-black with a broad, crescent-shaped sash of yellow and a yellow tail. The dorsal fin has 12 spines and 19-20 soft rays and is elongated into filaments which trail behind the fish as it swims. The anal fin is also extended by filaments and has 3 spines and 18-20 soft rays. The pectoral fins have 17-18 rays. The juveniles have an altogether different appearance. 
They have a base colour of steely blue with a number of vertical, meandering stripes of white and pale blue
The Arabian angelfish is found along the eastern coasts of Africa. Its range extends from the Red Sea and the Gulf of Adento Zanzibar. Its habitat includes sheltered coastal reefs with hard and soft corals, rocky reefs.
— Text and pictures by Khaled Zaki, a diving consultant, PADI ambassador, and UW photographer 
@khaledzakidiving