Environmental modeling of ocean net-pen aquaculture is driven by predicting how solid materials fall through the water column to the seafloor. Model parameters of sequential ocean flow vectors and the mapping of the benthos all contribute to calculating where the falling solids stop moving and interact with the seafloor. One crucial model input parameter is the velocity at which fecal materials fall through the water column by gravity. Salmon fecal settling velocities, density, and shape factor drag coefficient have been investigated on multiple occasions and are the default values in major net pen models since salmon producers are the primary model consumers. It is anticipated that net pen aquaculture will expand into the Gulf of Mexico cultivating warmer water species than salmon such as red drum (Sciaenops ocellatus ). We are investigating red drum fecal settling velocities and mass fractions using various feed types and fish sizes to better understand if and how settlement behaviors are different from salmon. To do so, we have constructed a flume apparatus capable of measuring the range of fecal settling velocities and the mass fraction that falls at the different velocities.