Phytoplankton in coastal upwelling regions undergo a conveyer belt cycle in which subsurface populations are transported upwards with upwelled water masses to seed surface blooms and return to depth as upwelling subsides and nutrients are depleted. Surviving cells at depth may act as seed stocks when upwelling returns. Here, lab-based upwelling conveyer belt cycle simulations were conducted with the diatom Emiliania huxleyi under low and high iron conditions.