Archeologists cannot say for sure what the lead pipe which penetrates the hull of a nearly 2,000 years old wreck of a Roman ship off the town of Grado in Italy was used for.   Some think that it was a supply line to an onboard  tank  which carried live fish to market.  If so, the approximately 55′ ship may have carried on one the earliest onboard fish tanks.

Is this the world’s oldest fish tank?

“Historians think that before the invention of the freezer, the only possibility to trade fish was to salt or dry it, but now we know that it was possible to move it alive also for quite a long distance,” researcher Carlo Beltrame, an archaeologist at Ca’ Foscari University of Venice, told LiveScience.

A number of texts from antiquity have contentiously suggested the ancient Romans could transport live fish by sea. For instance, the scientist, Roman officer and historian Pliny the Elder spoke of transport of parrotfish from the Black Sea to the coast of Naples.

They estimate an aquarium behind the mast of the ship could have measured about 11.4 feet by 6.5 feet by 3.3 feet (3.5 m by 2 m by 1 m) for a capacity of approximately 250 cubic feet (7 cubic meters). For comparison, an average bathtub has a volume of about 7 cubic feet. If properly maintained, it could help keep at least 440 pounds (200 kg) of live fish such as sea bass or sea bream, they noted.

“This simple apparatus implies that, as attested by some ancient authors, the trade of live fish in antiquity was possible,” Beltrame said.

Intriguingly, the researchers added that the Istria coast, which is only a few hours by boat from Grado, was known for numerous vivaria — enclosures for keeping live animals. Perhaps ships capable of transporting live fish brought such cargo to large markets, the researchers speculated.

Thanks to Irwin Bryan and Alaric Bond for the passing the article along.