Simulation of an air diffuser into a water tank - abnormal results

I'm trying to simulate the effect on water of an aerator in the bottom of a water filled tank using SolidWorks 2019.

I have created a basic model of the diffuser inside a tank, defined the air source, and tried to make it as simple as possible (a cylindrical tank with a solid split into a water space and air space).

Here is a video of the first attempt (that almost looks right - but it is deceiving in this case):

https://youtu.be/xfqcDNFNntY

I run into a couple problems.

If I adjust the air source to what it should be (0.002 m3/s instead of 1 m3/s), the particle simulation does not work. I would describe it as if the "air particles" do not rise in the water.

The second issue is more visible as I increase the number of particles: the more I add, the more I see that go from the air space into the water space. It would be like the water body does exist, or if the air was heavier than water.

https://youtu.be/_RpZxWESZMA

I'm new to this and I'm trying to also visualize the water movement within the tank, as a result of the air mixing the fluid, but I would like to get an accurate model first (of the air flow). I looked at a lot of videos and this is as close as I could get while obviously still not setting up all my parameters correctly somehow.

Thank you in advance for your help.

SolidworksFlow Simulation