The output and particle size distribution of several series of aqueous solutions were measured to define quantitatively the practical limits of the solution properties acceptable for aerosol production by the aeroneb micropump nebulizer. Aerosol output measurements were made gravimetrically and the particle size distributions were obtained by laser diffractometry. Solution properties were obtained from the literature by interpolation of the best-fit curve of the property plotted as a function of composition. For nonionic solutes, addition of sodium chloride dramatically increased the output rate and also decreased the droplet size at low solute concentrations. Increasing viscosity also caused a significant decrease in output. Cesium chloride displayed increased output rate with concentration due to the rising density. Based on calculations with the number of apertures and oscillatory frequency, low output rates appeared to be a consequence of apertures failing to produce a droplet with each oscillation. Overall, ionic strength, density, surface tension, and viscosity affected the output rate in a manner that can be now empirically predicted.