systems , apparatuses and methods for circulating and agitating algae ponds or reservoirs are described . inflatable or floatable masses resident in the algae ponds are cyclically or rhythmically moved thereby causing propagating waves to advance along ponds . waves encourage increased equilibrium of oxygen and carbon dioxide between ambient air and growth medium and thereby improved growth of algae and increased production of biomass . with relatively little energy input , large quantities of algae or biomass may be grown in relatively large ponds and on an economically viable commercial scale .