Automatic back-washing mode:When the pump sucks the water from the fish pond to the inlet bin of the micro-filter and flows into the drum, the drum filter net accumulates foreign matter to a certain amount to block, resulting in reduced water output, the inlet bin water level rises, the liquid level sensing switch automatically opens, concurrently,the controller opens the back-washing mode?1? Put the water pump into the fish pond?connect the outlet pipe with the micro-filter inlet pipe 2: The water outlet is a natural outflow to the fish pond, the pipe diameter can not be less than the factory configuration, otherwise the micro-water level is too high, the machine starts continuously 3: The sewage pipe can be connected to the sewer or stored for use as fertilizer 4: After the pipe is connected, plug in the controller power supply,When the device is delivered, the controller has been adjusted to automatic mode by default. .diameter Specification ?Inlet diameter 2-1/2"(73mm)outlet diameter 4"(114.3mm)Sewage diameter1-1/2(48.25mm)Product size?35“*23”*23“ All metal components are made of 304 stainless steel.