On December 20, in Luoyang, Henan, Ms. Zhang used a straw to clean waste from her fish tank. When the straw was submerged in the water, the water suddenly started freezing and quickly spread throughout the tank, trapping the fish in ice.

Ms. Zhang hurriedly turned on the heater, and after the ice naturally melted, the fish miraculously came back to life.

Experts explained that under extremely low temperatures, the water in the fish tank might have been in a supercooled state—water below its freezing point but not yet frozen. This occurs because, in the absence of nucleation points (such as dust or impurities), water can remain liquid even at sub-zero temperatures.

When the straw was inserted into the supercooled water, it introduced nucleation points, such as tiny air bubbles or impurities on the straw. These nucleation points triggered the alignment of water molecules to form ice crystals, initiating the freezing process. Since supercooled water is unstable, the freezing spread rapidly, causing the entire tank to freeze and creating frost patterns.

As for the fish surviving the freezing, it is likely because the process was so quick that it did not cause the fish’s cells to rupture, allowing it to survive and recover after thawing.