Repetitive pumping of damage sensitive species, with a vacuum pump, often causes high rates of stress and occasional mortality. Introduced in 1988, it took two years to design. They do not come in contact with any hard surfaces during transfer. In that regard, they tend to maintain their quality.
Higher quality is reflected in a higher market value.
Fish transferred with a standard vacuum pump are crowded together into the tank and then exit through a discharge hose. These systems tend to increase the stress level of the fish. Poorly designed vacuum systems, can even cause physical damage to the fish. The flow is continuous in the system, maintaining a high flow rate in the fish suction hose. For this reason, the fish do not have to be crowded to the extent required when using a standard vacuum pump.