Matala Hakko Air Diffusers with Included Base Diffuser Type:MDB22 (Large Base / Two 9" Diffusers) The check valve will prevent

The check valve will prevent water in the filter from back-flowing into the skimmer when the pump is switched off and keep water in bogs when the pump is turned off and other purposes

problem causing nutrients and murky water in water gardens and Koi ponds

Ammonia-Away removes deadly ammonia

5" - 3" 1000 10

Pulls debris from the bottom of the pond

Matala Hakko Air Diffusers with Included Base Diffuser Type:MDB22 (Large Base / Two 9" Diffusers) The check valve will preventMatala Hakko Base Air Diffusers are membrane air diffuser assemblies that feature heavy duty plastic bases with soft edges. These bases are hollow so that they can be filled with sand or gravel, eliminating the need for bricks and straps to get the diffuser to sink. Two sizes of bases are offered: the small base can accommodate one or two diffusers, and the large base can accommodate two or four diffusers. Heavy duty diffusers produce medium bubbles,