Aquarium - Constanta, the first section of the Natural Sciences Museum Complex, located on the seafront promenade Casino, in its immediate vicinity, is the first public aquarium in Romania and was inaugurated on the May 1, 1958.
The building that houses it was build at the beginning of the XX century, needed complete rearrangement, because it had a different destination before 1950. The Aquarium in Constanta remained the biggest institution of its kind in the country, even after other natural science museums have established departments with the same profile.The exhibition space is marked out for the presentation of the permanent aquatic flora and fauna exhibition in 57 tanks, and also for the temporary exhibitions with aquatic biological and ecological themes.An inedited museum institution for natural sciences in our country due to its exhibition patrimony made up entirely of living organisms, the aquarium in Constanta also has naturalized collections of marine and fresh water fish and invertebrates belonging to different geographical areas of the Earth.To facilitate the presentation of aquatic life and the visitors' access to information, the exhibition patrimony consists of over 100 species (1300 exemplars) aquatic creatures and is structured into several sections. The distribution of aquatic organisms into sections is based on ecological and bio-geographical criteria, and within the sections the taxonomic criteria was taken into account for placing the different species into the tanks.
The marine section
This section includes species of fish and invertebrates from the Black Sea and Mediterranean migrants.

This is the largest and most representative section of the Aquarium, both in capacity and importance of species in the tanks presented. The largest tank (30 m3) includes the biggest collection of sturgeons famous for its scientific importance and for the longevity of the exemplars in captivity (18-20 years). In this section are presented four species of sturgeons (Beluga, Starry sturgeon, Danube sturgeon and Sterlet), that are ponto-caspian relicts, some exemplars exceeding 150-180 cm size.

The non-economic species are also interesting for the visitors, being less known, such as: common stingray, black scorpion fish, greater weever, peacock wrasse, sea horse, deep-snoted pipefish, pipefish, rusty blenny, butterfly-blenny, etc.A special attraction for the public visitors is the presence of the reef tank with clown fish, surgeon fish, azure and white ladies and sea urchin.
The fresh water section
The fresh water section presents species of invertebrates of fresh water, populating the pools and costal lakes on the seacoast and the Danube Delta waters. Predator fish such as wells catfish, pike perch, perch, common pike, are also presented beside the well-known species of cyprinids: carp, gold fish, rudd, roach, common bream.
Exotic fish

The exotic ichtyofauna is also very well presented, belonging to different fresh water ecosystems in the tropical and subtropical areas of the continents Asia, Africa, America and even Australia.

The particular variety in color and form of more than 50 species populating the 4 sections of exotic fish among which: 3 varieties of piranha fish, knife fish, angelfish, paddlefish, catfish, etc.