Siphon refers to filling an inverted U-shaped tubular structure with liquid by using the force phenomenon of liquid level height difference, placing the high end of the opening in the container filled with liquid, and the liquid in the container will continue to flow out of the opening at a lower position through the siphon.
According to the above definition, which of the following is not a siphon phenomenon?
When Xiao Wang changed the water for his fish tank at home, he squeezed out the air in the pipe, then inserted the pipe into the water, and the water source kept flowing out.