We are trying to use the MP3V5004GP to build a wireless sensor node which will measure water level in a tank (depth 1 meter). The problem is that the sensor output starts dropping even though the water level is constant. We are using Tygon Lab Tubing (Non-DEHP, 3/32"ID X 5/32"OD). The node electronics (including the MP3V5004GP with one end of the tube attached to it's port) is outside the tank and the other end of the tube is at the bottom of the tank. The tube is a pretty tight fit (tube ID is smaller than port diameter) and is not easy to detach from the port but we still see water enter the tube leading to drop in sensor output. I even tried permanently gluing the tube to the sensor port. I recently came across AN1513 which suggests using hose clamps to reduce leakage. Can you help me us selecting the right hose and clamp for the MP3V5004GP ?