Try Corsair Diving Centre in Bugibba -
Corsair Diving Centre Malta, Scuba Diving Malta, Holidays in Malta Gozo Comino, PADI diving. They do recreational diving from a modern, purpose built dive centre in Bugibba - and they're PADI 5 star.
I can highly recommend Melita, Director of Diving, and Kevin. Melita has been teaching my son since he was 14 years old. He's now an 18 year old Divemaster, thanks to Melita's great tuition, and he wouldn't go to anyone else in Malta. In fact he intends taking the Assistant Instructor course with them. They're fun, safe - which was important to me of course - and they also have excellent equipment (which incidentlaly is all new this year).