A 50-foot-high, 264,000-gallon cylindrical tank called AquaDom, housed in a Radisson in the German capital, spectacularly collapsed, sending waves of water through the building and onto the street. The entrance to the five-star hotel looked like a bomb site. Mangled Christmas decorations, twisted poles and window frames, even tiny shampoo bottles littered the street — and among them, the bodies of the blast’s victims: nearly 1,500 tropical fish from a 50-foot tank called the AquaDom. Any sea creatures that survived the initial blast of the cylindrical AquaDom, billed as the largest tank of its kind in the world, had little hope of rescue. In frigid, 19 degrees Fahrenheit weather, they lay frozen on the street outside the Radisson Hotel, in Berlin’s central Alexanderplatz. “It’s a tragedy for the fish,” said Markus Kamrad, an official at the Berlin Senate responsible for animal protection. “We were lucky that it happened at a time that only two people were slightly injured. But it’s unfortunate, of course, that so many fish died.” The tank burst at 5:45 a.m., rescue services said. Had it happened later in the day, the result could have been human tragedy, too. The AquaDom, in the center of the hotel atrium, had a diameter of 38 feet and was wrapped around a glass elevator, where visitors could view the sea life inside. Police officers at the scene shook their heads at the thought of what could have awaited them had the tank broken just a few hours later in the day. Even hours after the AquaDom burst, an entire block of the street outside the building remained soaked by 264,000 gallons of water that rushed out of the lobby, uprooting plants and ripping out telephones that lay strewn among hundreds of chocolate balls from a neighboring Lindt chocolate shop, also battered by the force of a wave of water that local media estimated would have weighed about 100 tons. The impact of the water erupting onto the street was so powerful that local seismographs picked up on it. Several shops nearby were damaged — with chairs upturned and windows shattered. The police have said they have no suspicion of foul play. Local media said the cause was likely a technical fault. In the early afternoon, a special rescue unit of Berlin firefighters rushed to the scene, wearing hard hats and equipped with carabiners and ropes: They were going to scale the top of the tank, and descend deep into the buildings’ basements.