STORY: A colony of Gentoo penguins - which hail from Antarctica - slid around on a layer of ice in their sealed enclosure.
Staff fed them on small fish from containers of ice. The colony is coming to the end of their annual mating season, which usually runs from March to July, Sea Life London Aquarium said.
Another resident of the aquarium, Shakira the octopus, helped herself to a meal of squid from a yellow bucket.
Britain was on course for its hottest day on record on Monday with temperatures forecast to hit 40C for the first time, forcing train companies to cancel services, schools to close early and ministers to urge the public to stay at home.