[hn_is_vile]

The problem with this particular experiment is the speed and scale of it. Both iron sulphate and iron oxide are being 'dumped' in the ocean all the time, by the world's rivers. The difference being the level of dilution.

Algal blooms != algal growth. Algal growth is healthy for the ocean, marine life and the oxygen breathing carbon based life forms inhabiting the land masses of the planet.

Algal blooms on the other hand, have none of those characteristics, can lead to anoxia in the area of the bloom, which kills marine life and results in the algae decomposing back into CO2.