Low sequestration estimates that emerged from some ocean trials are largely due to three factors that make the findings unreliable:
- Timing: none of the ocean trials had enough boat time to monitor their blooms for more than 27 days, and all their measurements are confined to those early weeks. Blooms generally last 60~90 days with the heaviest precipitation occurring during the last two months.
- Scale: most trials used less than 1000 kg of iron and thus created small blooms that were quickly devoured by opportunistic zooplankton, krill and fish that swarmed into the seeded region.
- Academic conservatism: having an obviously limited data set and unique sequestration criteria (see Sequestration Definitions below), many peer-reviewed ocean researchers are understandably reluctant to project or speculate upon the results their experiments might have actually achieved during the full course of a bloom.