Opuntia spp., a type of cactus, grows in many water-scarce regions. This plant has myriad uses, ranging from cuisine in some cultures to cattle feedstock to coagulating agent for water clarification. This project investigates Opuntia spp. for application as a point-of-use water treatment technology. Unlike some coagulants used in centralized water treatment, Opuntia spp. is of natural origin, renewable, and not associated with any ecotoxicological or human health concerns. Opuntia spp. is able to remove 98% of turbidity from synthetic turbid waters, and it was recently hypothesized that Opuntia spp. operates through a bridging coagulation mechanism. The active agents responsible for coagulation have not yet been isolated. This research establishes which parts of the Opuntia spp. cladode demonstrate coagulation activity. In addition, results on the charge, size, and molecular form of the active agent are presented.