Is it the ribbed tubing? If so, go to Home Depot. Get the right sized vinyl tubing. The ribbed tubing is notorious for leaking when you try to plumb in-line devices.
Then replace the ribbed outflow tubing with the new vinyl tubing and plumb in your peripherals and use hose clamps.
I know people have successfully plumbed in things and have kept their ribbed tubing, but I replaced all of my tubing with vinyl tubing and I like my current setup very much. Don't have the worry of something leaking in the future.