View from SeapiX > Service Information:
Any No Connections part showing in red invites you to check the BFU-VPU connection.
It has been designed to display or hide
sedimentary zones (silt, sand, rock,
gravel etc.) according to data from official
maps or data acquired from the sounder
you are using. This data can be
displayed in the main 2D view as well as
in the 3D view.