I have just bought a new Oase Pondvac 4. Once the first chamber fills, I notice water seeping and bubbling out all around the area where the vents are on the sides of the motor. The unit empties properly, but instead of regaining suction, the motor shuts off. I then have to wait about 20 minutes until the unit will turn on again. I've checked for clogs and cleaned filters but it continues to happen. I've contacted the place that I bought it from but they haven't ever actually used one. I'd hate to have to return it. I'd love to get it to work properly.