Video of a lake filled with ash

Per Google translate, "Diver trying to swim in the lake Nahuel Huapi, which is covered by a thick layer of volcanic ash emitted by the volcano Puyehue." Via.

AquaDom in Berlin

The AquaDom is in the Radisson Blu Hotel in Berlin:

The AquaDom belongs to the Sea Life Berlin. In the neighbouring tour of Sea Life Berlin, visitors discover 30 fish tanks containing local species from the River Spree to the Atlantic Ocean. The highlight of the tour is a ride across the AquaDom, the world's largest cylindrical aquarium, where a multitude of tropical fish reside in one-million litres of salt-water.

AquaDom facts:

Habitat to over 1500 tropical fish and over 50 different species including trigger fish, hogfish, humphead wrasse (Cheilinus undulatus), blowfish (Tetraodontidae), surgeonfish (Myripristinae), soldierfish (Tetraodontidae) and swarm fish, like Cero mackerel (Scomberomorus regalis) and Silver moonfish (Monodactylus argenteus).
Height of the AquaDom is 25 metres.

This first video shows construction, the exterior, and the interior of the aquarium:



And this second video is an unedited ride in the elevator:



There's lots more photos at Flickr. Via.