Penn Plax Bubble Wall Diffuser 18″ SKU: PPX36 Category: Aquarium Accessories Related products Ammorid Insert Aquaclear 150 / 30 2in1 Fish Hatchery Foam Base 12×18 (use for 18″ wide Tanks) (PKT 10) Aquafx 2ft Cabinet & Hood White 24×12 Assembled (Pickup or local delivery only)