Many gelatinous zooplankton consume a large amount of prey and have stomach volumes much greater than the volume of individual prey. We suggest that jellyfish can use their voluminous stomach as a buffering food-accumulating organ that allows the organism to feed at maximum clearance rate in a wide range of fluctuating food concentrations. The food accumulation capability was confirmed for the hydromedusa Sarsia tubulosa feeding on copepods. Starved jellyfish feeding in high prey concentrations for 1 h displayed much higher average ingestion rates compared with jellyfish feeding for 20 h or with jellyfish that were pre-adjusted to the food concentration before incubation. The findings have implications for design and interpretation of experiments. The possibility for jellyfish to feed at maximum clearance rate in either very high prey concentration for a short time or low prey concentration for a long time was illustrated with calculations of prey uptake by S. tubulosa feeding in prey concentrations of variable heterogeneity. The ability of jellyfish to capture prey at maximum clearance rate under different prey concentrations, and to accumulate relatively large amounts of food in their guts, suggests that they would thrive in both homogenous and patchy food distributions. This property may have contributed to the evolutionary and ecological success of the medusoid 'bauplan'.