Anaerobic digestion is the process where microorganisms break down organic matter in the absence of oxygen. In digesters, adding ExtremeDuty™ Sludge Mixers can prevent stratification and improve the anaerobic digestion process. The Blue Frog^TM Circulator can be a stand-alone system or one augments other lagoon technologies (i.e. fine bubble aeration) to digest sludge and reduce BOD & TSS; eliminating costs to handle sludge. All circulators, covers, holders and mixers below are distributed by Nulantic Water.