Fluval FX5 output problem

I picked up one of these from craigslist for $100 about a month and a half ago.Worked great and I tested it with the original owner. Had to buy the media but that was not a big deal. The output nozzle does not seem very stable though. When the water comes out I can see it sort of moving which is not a problem, but it slowly shakes it loose or sometimes off all the way. I have to put my hand in the tank and re-secure to the hose. Is there anything I can do to connect those parts so I can avoid it? When it comes off completely the output just rips into the sand and makes a huge mess. I was thinking some sort of tie down or would it be better to replace it