Thanks from welcome greetings,
You should definitly visit Croatia sometimes. Maybe Adriatic sea is not known to you yet but it is more interesting then many world famous world diving locations.
Here in Croatia, we have many ship wrecks which are not investigated at all.
For example, only around island Vis (in the middle Dalmatia) there are maybe a douzen ship wrecks of big navy ships. They are dating from famous naval Battle of Vis in 1866.
The Battle of Lissa took place on 20 July 1866 in the Adriatic Sea near the island of Vis (Italian: Lissa) and was a decisive victory for an outnumbered Austro-Hungarian force over a superior Italian force. It was the first major sea battle involving fleets using iron and steam, and one of the last to involve deliberate ramming.
Many of ship wrecks still expecting to be investigated.
Also, here are many ship wrecks from WW II. Some of them you can visit with the organization of the local diving centers for the relatively small price (around 30 euro). Not to mention ship wrecks from Middle ages and Ancient times....
It is hard to say where is more interesting to dive.
For example national park Kornati near the Sibenik has a crystal clear sea with very rich underwater life, the coast around islands Brac, Hvar, Krk, Komiza.....
The environment and nature are typically Mediterranean, with imposing walls, drop-offs, caves, caverns, crevices and wrecks. The waters are renowned for their clarity, with vivacious colors and encrusted sponges, big sea fans of red and yellow, concentrations of red coral, nudibranchs, mollusc's and crustaceans (also of large dimensions). The aquatic life is very developed, you will see a lot of cliff fish and meetings with pelagic fish are not rare, particularly above the drop-offs (beyond 20m). Dives of archaeological interest are also possible.
.....you can dive wreck of fishing boat Pajo on southern side of Island Čiovo, (near airport Split) is atractive diving location on whom beside conture of beautiful grassy wreck of fishing boat you can see rich underwater vegetation and life of southern side of Čiovo island, or dark cave Zmajevo oko (Dragon's eye) on island Brač and if you have luck to see pack of huge „Gofs“ Seriola dumerili fish, that are mostly hidden there. Cave entrance is on 3 meters depth and cave goes all long to 37 meters of depth.........I could write for days.....
All in all, you can't menage to visit all of the interestin diving locations in Croatia even if you live 300 years.
You are all welcome!