The trends that promote anionic reagent adsorption and subsequent flotation were examined in a statistically designed study in an effort to determine their effect on reagent mixing during anionic conditioning on a bench scale. The impeller power was measured during conditioning, and a statistical model was developed to correlate impeller power to the various conditioning variables examined. It was observed that the impeller power was significantly affected by the conditioning variables. A range of solids loading and agitation speeds exists in which the classical power number-Reynolds number correlation was found to hold true. The impeller power was found to be influenced by the conditioning time, indicating a time-dependent variation in theological properties of the phosphate feed slurry. It was suggested that the impeller power drawn during conditioning was an indication of the extent of mixing of the collector with the particles, which contributes to the reagentization of the phosphate particles and their subsequent flotation. Flotation recovery was found to decrease when conditioning was carried out in the regime where the impeller power deviated from the N-P-N-Re correlation.