Dilute aqueous suspensions of finely divided mineral waste from phosphate ore beneficiation were allowed to consolidate in the presence of eitherAnacystis nidulansorAnabaena cylindrica.Addition to this mineral suspension of 2.2 mg (dry weight) of freshA. nidulansper milliliter of suspension resulted in solids consolidation that exceeded the untreated control by 65% after 11 days. When freshA. cylindricawas mixed with the slimes suspension, no enhancement of consolidation occurred. Addition of either 1 mgof dryA. nidulansor 1 mg of dryA. cylindricaper milliliter of suspension resulted in consolidation that exceeded the untreated control by 25% after 9 days. Direct addition of A.nidulansto the process water of facilities relying on gravitational dewatering of such mineral suspensions could reduce the residence time in the initial settling ponds. Whether such a process would affect long‐term settling is unknown.