My sister in law has given us a 75 gallon aquarium with a AHEIM professional filter cannister. I have filled the cannister with water and when you turn it on the water will come out of the bubble bar for a bit and then stop and then nothing happens. I am wondering if there is something I am doing wrong. It burps a few times but nothing else. Please let me know if you have one of these. And it does not have a primer button on it anywhere.