Also worth noting: Sudan’s Red Sea is mind-blowing if you’re up for a more adventurous trip. Less crowded, amazing walls, and sites like Sha’ab Rumi—Jacques Cousteau’s old underwater base is still there!
For Thistlegorm, Advanced Open Water is usually required because it’s around 30 meters. And a wreck specialty helps, especially if you plan to penetrate the structure. For places like Brothers or Daedalus, guides often prefer you to have 50+ dives, since currents can be strong.