Purpose: To evaluate the influence of nutrient availability on cellular elemental composition (quotas and stoichiometry) in marine picoeukaryotes.Summary: Elemental quotas and ratios are assessed under nutrient replete and deplete conditions at the same time to minimize potential variation between experiments. Cells from an exponentially growing culture are concentrated by centrifugation, washed and re-suspended in a small volume of nutrient deplete media. These concentrated cells are used to inoculate triplicate replete and deplete culture flasks at a starting density corresponding to early-exponential growth. Culture growth is monitored daily. When the mean growth rate of the nutrient deplete treatment is half or less of the replete treatment (GRDEP\/GRREP < 0.5), samples for cell counts and elemental analyses (dissolved nutrients; particulate carbon, nitrogen, and phosphorus) are collected.