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The air effects stop affecting particles once they exit the Simulator thus altering the particle speed and direction around the Simulator's walls.

When running liquid simulations with the Initial Fill Up option and Open Container Wall conditions, the surface of the generated liquid should remain smooth. If you encounter artifacts in the form of horizontal lines perpendicular to the direction of movement, with Motion Inertia enabled, please ensure that the Scene Scale is reasonable considering the type of effect being simulated. Other possible solutions in case tweaking the scale is not possible are to either increase the Steps Per Frame, or to reduce the Cell Size of the Simulator.

Liquid artifacts usually appear when the liquid particles move a great distance between frames. Increasing the Scene Scale or the Steps Per Frame allows them to stabilize, which in turn keeps the surface smooth.

The liquid created through the Initial Fill Up option will be initialized with the values set for the Default RGB and Default Viscosity parameters below.

All Simulator walls must be set to Open from the Grid rollout for Fill Up For Ocean to take effect.

One of the most important parameters of the Simulator, with significant impact on quality and performance. To understand how to use it, keep in mind that the simulation is a sequential process and happens step by step. It produces good results if each simulation step introduces small changes, but it's also a trade-off between performance and detail, as described below.

For example let's take an object that is hitting the liquid surface with high speed. If at the first step the object is far away from the water and at the second step, the object is already deep under the water - the result won't look good. You have to introduce intermediate steps until the changes of each step get small enough. The Steps Per frame option creates these steps within each frame. A value of 1 means that there are no intermediate steps and each step is exported into the cache file. A value of 2 means that there is one intermediate step, i.e. each second step is exported to the cache file while the intermediate steps are just calculated, but not exported.

Signs that the Steps Per Frame need to be increased are:

More often than not, those issues will be caused by the simulation moving too quickly (e.g. the emission from the source is very strong or the objects in the scene are moving very fast). In such cases you should use a higher SPF.

Keep in mind that higher Steps Per Frame decreases the performance in a linear way, i.e. if you increase the SPF twice, your simulation will go twice as slow. However, the quality does not have a linear relation to the SPF. Each simulation step kills fine details, and thus for maximum detail it's best to use the lowest possible SPF that runs without any of the issues mentioned above. For additional information, please refer to Phoenix Explained.

In order to achieve the same simulation look when changing the Time Scale, the Steps Per Frame value must be changed accordingly. For example, when decreasing the Time Scale from 1.0 to 0.5, Steps Per Frame must be decreased from 4 to 2. All animated objects in the scene (moving objects and sources) must be adjusted as well.

Time Scale different than 1 will affect the Buildup Time of Particle/Voxel Tuners and the Phoenix Mapper. In order to get predictable results you will have to adjust the buildup time using this formula:
Time Scale * Time in frames / Frames per second

The RGB Grid Channel has to be enabled in the Output Rollout for this parameter to take effect.

• All FLIP liquid particles are set to this viscosity value at simulation start. You should use higher viscosity for thicker liquids such as chocolate, cream, etc.
• The Default Viscosity is also used for the fluid generated by Initial Fill Up, or by Initial Liquid Fill from the Chaos Phoenix FD Per-Node Properties of a geometry - both of these options create liquid only at the start of the simulation.
• If a Phoenix FD Liquid Source does not have Viscosity enabled, it emits using the Default Viscosity value.
• During simulation, liquids of variable viscosity can be mixed into the sim by using a Phoenix FD Liquid Source with Viscosity enabled.
• The Viscosity Grid Channel export has to be enabled in the Output Rollout for variable viscosity simulations to work.
• The viscosity of existing liquid can be changed over time by using a Phoenix FD Mapper in order to achieve melting or solidifying of fluids.
• You can shade the liquid mesh or particles using the fluid's viscosity with the help of the Phoenix Grid Texture or Particle Texture. 
• It's important to note that using viscosity does not automatically make the liquid sticky. For example, molten glass is viscous, but not sticky at all. Stickiness can be enabled explicitly from the Wetting parameters section. If Stickiness is not enabled, even the most viscous fluid would slide from the surfaces of geometries or from the jammed walls of the Simulator.

Geometry transforming or deforming at a high velocity may cause some or all of the Wetting particles stuck to it to disappear. To resolve this, dial up the Steps Per Frame parameter from the Dynamics tab of the Simulator.