The flow regimes of rivers in Australia’s Murry-Darlin Basin have been modified by water resource development. Changes in hydrologic connectivity and flow variability are expected to alter the quantity and quality of the food resources available to consumers. For instance, low and stable flows may increase the availability of high-quality algal resources, while floods may increase the prevalence of lower-quality terrestrial detritus. Omnivorous decapods such as glass shrimp (Paratya australiensis) are abundant consumers that feed on a variety of food sources in these dynamic riverine ecosystems, but how their growth rate is affected by changes in the quality of food resources is not well understood. Here, we experimentally tested how diet quality affected the growth rate of glass shrimp (Paratya australiensis). The shrimp were held in aquariums and fed diets representative of the different quality of food resources available in natural systems for six weeks: algal pellets, blood worms, fresh leaf litter, and conditioned leaf litter. We expected that those fed a higher quality diet (i.e., algal pellets and blood worms) would grow significantly faster than those on the lower quality leaf litter diets. In the initial three weeks, shrimp showed no significant differences in growth (length and mass) among diet quality treatments. However, between weeks three and six, the shrimp fed on agal pellets grew significantly more than those fed on leaf litter. Our results demonstrate that diet quality can impact the growth rate of decapod omnivores that are important prey to higher trophic levels such as fish and waterbirds. This suggests that changes in flow regimes or other disturbances that alter basal resource quality will have an impact on the boarder food web.