Resistive water level sensor with good sensitivity

Does anyone knows about a good resistive water level sensor compatible with Cerbo GX and good accuracy, meaning numerous and short steps of resistance ranges. I have a tank with a special shape to fit above the van wheel and the current sensor I used has only a few steps of resistance in its highest portion , where I would need more numerous and smaller steps between 2 resistance readings . I used an Osculati sensor of 60 cm but its resistance curve is not suitable for my tank. Thanks for your help