Aquarium surface water extraction equipment - has self-regulating hydrostatic valve below stand-pipe outlet and preferably detachable

摘要

The equipment extracts surface water from an aquarium, having a standpipe with a water inlet at the top and an outlet below it connected by a pipe to a suction filter. Below the outlet (15) is a self-regulating hydrostatic valve (16), pref. detachable from the standpipe (12). The valve can have two chambers (17,20) open to the water basin and the standpipe, and connected together via a valve opening (21) controlled by a plug (22). Buoyancy forces in the first chamber thrust the plug upwards (24), while its weight and the hydrostatic pressure inside the standpipe thrust it downwards (26).