Hello all, we are researching devices/gadgets to determine the level of LPG in our twin Gaslo refillable system, 11kg and 6kg. We’ve previously winged it and so far been lucky to gauge the level correctly but it would be good to actually know a precise level to take away the guessing. Do any of you lovely people have a branded system that you would recommend ? We‘ve looked at the Truma system, theirs use an app and pen but it would be great to have some feedback from anyone who uses this system or any other system successfully. Any advice would be much appreciated thank you.