Algae sequestration

I have been looking around for how much CO2 algae sequestors per unit.

Best info so far is 1.25-1.75 tonnes of CO2 per of tonne of algae. Which is good. Less mass of algae than for pure CO2 (presumably because photosynthesis produces oxygen and stores carbon).

So we need to bury 1.00/1.5 (middle) X 780 X 10^15 = 520 billion tonnes.

How about in the sediments at the bottom of the ocean? plenty of room!

How much CO₂ can be utilized by growing 1 tonne of algae?

This ultimately depends on the algae strain and available nutrients, however, 1 tonne of algae can sequester about 1.5-1.75 tonnes of CO_2. CO₂ consumption is based on the overall lipid-protein-carbohydrates balance of the final algae. CO₂ incorporation is ultimately based upon the overall algae composition that results in the macromolecule composition of the harvested algae. These macromoleculesmolecules are between 40 and 80% carbon with an average composition of 50% carbon.

http://www.dynamicbiogenics.com/page1.html