particleEmitter.Simulate doesn't work

I have a waterfall script, and when I have:

public float initTime;
public ParticleEmitter waterfall;
 
void Start(){
    waterfall.Simulate (initTime);
}

Only a small chunk appears first instead the whole thing! I even did a ‘for’ loop and that didn’t work either. Is this just glitchy? Other people obviously can’t get it to work like me. Is there a solution yet?