Freezing water expands. What if you don't let it? The first 200 people to https://brilliant.org/minutephysics get 20% off an annual premium subscription to Brilliant. Thanks to Brilliant for their support.
REFERENCES
Page with TONS of info about water and ice
https://water.lsbu.ac.uk/water/water_density.html
Specifically, a graph showing densityphysics LINK