Although I don’t only show things you can try at home, I try to provide a large proportion of posts that you can - and here is another easy experiment to try at home.
First take a cup of water and cool it in the fridge or freezer. Second, take another cup of water and add a small amount of food colouring to it. Heat this second cup (be careful) in a microwave or a saucepan. Once this is done carefully pour the heated, coloured liquid onto the colder water. Hopefully two layers will form due to the different densities of the liquids. As the cool water warms up and the coloured liquid cools down the densities change until eventually the coloured water is denser than the layer below.
This situation triggers the Rayleigh-Taylor instability and will hopefully form similar fantastic images to those above.
Photo credit: Physics central