Make a convective cloud at home!

• Use a pipette to inject 5 ml of single cream into a puddle at the bottom of a tank of cold tap water
• Support the tank with upturned cups and slide a polystyrene cup containing boiling water under the tank beneath pool of cream, while illuminating the tank from above
• Single cream seems to work best: it has roughly the same density as water and is a clearly visible tracer of the flow - milk is denser than water and too faint while double cream is lighter so a little bit buoyant before the heating begins (although it makes a very nice optically thick cloud).
• Food colouring is very disappointing in my experience: it doesn't illuminate very well in the light, and those that are glycerine based are too dense and stick stubbornly to the base of the tank even when heated
• The tank below is 40x25x25 cm in size, and the frames of the movie are 10 s apart