Our horse algae nutritional supplement contains the simplest of life forms: Aphanizomenon flos-aquae (AFA) [blue-green algae]. AFA is an aquatic plant only naturally found in Klamath Lake, Oregon. Knowing the source of your AFA guarantees its quality. E3 Equine quality control parameters, coupled with our proprietary, final processing, yields Klamath Lake's most potent source of AFA. We guarantee it!