The performance of the flocculator clarifier is compared to the performance of the units tested by the CRTC. Key research issues are identified as follows: 1) the effectiveness of scrapers vs. suction pickup, and 2) the need to compare the capacity of clarifiers with good response to surface overflow rate on a uniform basis with respect to solids loading. The latter research need is complex, as there is a need to test the ability of a clarifier to handle both its theoretical capacity in terms of being critically loaded with respect to its “solids flux” capacity (which relates to its sludge removal capability) but to also to its ability to handle inventory transfers without impacting effluent suspended solids.