Why Alu tank float?

[Clutchcargo]

Actually, ice is less dense than the surrounding water that's why it floats. Ice expands when freezing (ever had a pipe burst in the middle of winter - frozen pipes). So as the ice melts in the lake the water level would drop.

 

[RichLockyer]

Actually, ice is less dense than the surrounding water that's why it floats. Ice expands when freezing (ever had a pipe burst in the middle of winter - frozen pipes). So as the ice melts in the lake the water level would drop.

Nope.
That would only happen if the ice were anchored and held completely below the surface.

Go back to your basic buoyancy lessons. The volume of ice that appears above the surface when ice is floating IS the volume of air contained in the ice.

 

[Clutchcargo]

Lets see, there's got to be some kind of technicality I can hide behind.
Yep, you're right. Time to go back to my cave.