Our high-efficiency Fine-Bubble diffusers are designed to produce maximum water flow & lift. The extruded EPDM bubble tubing is very resistant to fouling and physically durable. Their rugged design will give you many years of reliable service and work great at any depth profile. Unlike cheaper disc-style diffusers, our DB-36 and the massive DB-72 have no membranes to clog or burst. In addition, they have extremely low back-pressure. All models include a LIFETIME WARRANTY.