Sargassum concrete blocks

https://youtu.be/X4rxSz8Oze0?si=D6LjXRZZvtAiEVXi

Pelagic Sargassum blooms have massively increased, littering Caribbean beaches - perhaps fueled by nitrogen runoff from Amazon deforestation. 

At the right proportions, sargassum with its lignin, cellulose, and polysaccharides

3:16 acts like rebar reinforcing the concrete blocks, making them twice as strong as conventional ones. 

The bricks also have 4:07 half the thermal conductivity of regular bricks, reducing air conditioning costs.