Imagine each oval ais a singular H2O molecule, but very big, you can change the radius of the particles to fill smaller areas more convincingly, the issue is more particles equals worse performance, so find the ballance you're cofortable between particle radius and particle limit, if you have a beefy enough machine, you might be able to afford to both have a radius of 1 and the 1000000000 particles simultaneously.

set blur passes to 4