The brownian motion setup using smoke and air particles represents and allow us to conclude that gaseous particles move randomly (in any direction). Is there a setup using other particles and another fluid instead of smoke and air to represent the movement of liquid particles? 1) Can we use Pollen grains and water? Or Red ink and water? 2) Is the choice of pollen grains practical? For e.g. solubility of red ink/ movement of red ink in water or the density of pollen grains compared water?