Particles are treated as points and can only be rendered with at least one instance object attached to the "Fluid" container. The random parameters are, for example, suited for "Granular" particles and turn RealFlow | Cinema 4D into a scatterer.
Render only
In order to → render → render the particles you particles you have to attach an object:
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When active, the fluid's particles are converted to Cinema 4D's → Thinking Particles → Thinking Particles (this feature requires Cinema 4D Studio):
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