Coagulation and flocculation have different jobs
A cationic organic coagulant can help destabilize fine suspended particles. After destabilization, process conditions affect how aggregates grow and how easily they can be separated.
Evaluate the process as a whole
A candidate grade should be tested with the actual water and the rest of the treatment sequence. Assess the clarified water and how the solids behave in the intended separation equipment.
For background on these treatment stages, see the Kemira Water Handbook and Veolia clarification handbook.