wtf is boardstromtank?

BoardstromTank is a small driver that lets a specific brand of tank sensor, the Boardstrom radar sensor, show up as a normal tank reading on a Victron Energy system. If you have a boat, camper van, or off grid setup with a Cerbo GX or similar Victron display running Venus OS, this project makes your water or fuel tank levels appear on that display, on the touch screen, in the VRM online portal, and over MQTT, the same way a wired sensor would. The Boardstrom sensor is a battery powered radar unit you fit to a tank without drilling extra holes. It measures the distance from the top of the tank to the liquid surface and sends that reading out over Bluetooth about once a minute. This driver runs on the Venus OS device, listens passively for that Bluetooth broadcast using the standard BlueZ Bluetooth stack, and turns it into a proper Victron tank entry. It does not connect to the sensor or interfere with it in any way, so the sensor keeps talking to its own companion app at the same time. Setup does not require editing configuration files. The easiest path is installing PackageManager first, a separate tool that manages Victron add-ons, then adding BoardstromTank as a package by entering the author's GitHub username and the package name. A manual install over SSH is also documented for people comfortable with the command line. Once running, the tank appears automatically in the Venus OS device list within a minute of the sensor broadcasting, using rough default calibration. To get accurate readings, you open the tank's setup page on the GX and enter two distance measurements, one for empty and one for full, while watching the live distance value update on the same screen. The project supports multiple sensors at once, each becoming its own tank on the display. It is described by its author as beta software, tested so far on a Raspberry Pi 4 running Venus OS. Support is offered through a Reddit community and a direct email address, and a log file lets you watch what the sensor is broadcasting if a tank fails to appear.