4"X 2" RETRO FIT BOTTOM DRAIN RING AIR DIFFUSER KOI FISH POND PUMP FILTER TANK

Diffuser Hose: 840mm of perforated hose. As gravity-fed pipework is typically laid beneath the pond and encased in concrete, bottom drains should be planned and installed during pond construction. Each drain consists of a sump set into the pond base and connected to pipework.

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