Use 6mm ID silicone tubing

Upright model using 2.38mm Alu tubing

Horizontal model uses 4mm ALu tubing ( you can close the ends with 6-32 set screws and loctite or just Squish the ends with pliers.

Both use M3 square nuts so the height can be adjusted by a bit.

Play with the amount of holes, too many holes will give you less air pressure.