It is part of the filtering system. The perforated pipe is laid in a loop under the gravel, the air pump sucks water out of the pipe. This in turn pulls water through the gravel bed.
@@edquince1 i wouldn’t know where to even look for that 😅😂 but I ended up opening it from the front driver side door with the air pump wedge and a hanger 😂
The perforated pipe allows the air pump to pull water through the gravel bed. This filters the water mostly through the bacteria that live on the gravel. Mosquitoes prefer still water but also they like to lay where there are few predators. A well established pond creates a complex ecosystem where mosquito lavae are soon eaten. There are some Mosquito lavae but less than in a water butt or puddle where they have no predators.
Go for it! It is cheaper and quicker to not build foundations and walls, and I liked the more organic look. However, you need the right ground type. I have heavy clay, so it was easy to shape and holds up well. The sides should not be completely vertical, and I think I was lucky there was no heavy rain after digging and before lining and filling with water. Hope that helps
Thanks. I am using a 40w air compressor (Hailea v60) to run the 6 air lift pumps. This circulates approx 150m3 every 24hours. Its a very energy efficient system.