How to know you are using the correct resolution?
Maybe this post can be simple for the most advance users but could help to newbies to understand the importance of the resolution parameter used in the emitters. You can detect the lack of resolution in your fluids if you see a thin layer of particles stuck to the side of the objects. Have a look to next videos.
This video shows an emitter with resolution set to 1.0, you can observe a layer of particles stuck to the side of the glass.
Next video shows that increasing the resolution to 10.0 you will rid of the layer, but if you look carefully you see there is still a layer on the top sides of the fluid.
In next video you can see the best results but maybe it is not needed to increase so much the resolution up to 50.0 and a value of 25.0 or 35.0 would be enough for this simulation. Obviously you can get better results with a better accuracy simulation but much more time to compute it will be needed.