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Mark Rober's CrunchLabs
Season 3 · Episode 3
Building a Liquid Sand Hot Tub
0.09mMarch 16, 2026
With the right amount of forced air, a hot tub filled with sand can look like a bubbling pot of soup. But how? Mark breaks down the science behind it.
Episodes
- Episode 1Lava vs Laser Destruction Test
- Episode 2Backyard Squirrel 2.0 - Bank Heist
- Episode 3Building a Liquid Sand Hot Tub
- Episode 4This Ball Is Impossible to Hit
- Episode 5Vortex Cannon vs Drone
- Episode 6Glitter Bomb 1.0 vs Porch Pirates
- Episode 7Engineers vs Food Robots
- Episode 8Mark Rober vs Ninja Kidz
- Episode 9Engineers vs Custom Go Kart Racing
- Episode 10Episode 10