Hey Pnut,
I have the same set up. Here is what worked for me:
Place the end of the tubing in boiling water for 30 seconds,
Push the tubing all the way down over the heater fitting and let cool,
Install small hose clamps and you should be good.
Make sure you get a temperature controller. Ranco is good. My Hydor was only about 16 months old. the thermostat failed and I lost an entire tank of fish.
I was going to get a temperature controller but never got around to it. Please learn from my mistake
Hope this helps.