This was a simple experiment into sand fluidization.  Turns out this was really fun.

I have not tested the tall bed yet.

Print Settings

I printed all of this at 0.3mm layer height.  

I used supports everywhere for the bed and supports from the plate only for the air tubing.

The air pump i used was this one https://www.amazon.com/dp/B08CSKJNDR?psc=1&ref=ppx_yo2ov_dt_b_product_details

And to watch a video of it in action go here