Yes, serves as excellent mulch, potting medium, and if still green the nitrogen and moisture will help jump start the composting process. If dried it still serves as an excellent source of carbon which is far easier to break down than newspaper, cardboard, etc. Algae is a miracle organism - can be processed into biofuel as well...lot's of organizations working on that project.

https://www.energy.gov/eere/bioenergy/algal-biofuels

Many men go fishing all of their lives without knowing that it is not fish they are after. ~ Henry David Thoreau

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