make sure you fill the cannister filter right to the top, give it a little wobble to get rid of most of the air bubbles.
connect all the pipes, connect the filter, and suck on the outlet pipe till you hear the filter sound like it is going, stop sucking.
If you are lucky you may have got a little black ball with the Fluvals which does the sucking for you.
When the 03 start running they are sweet.
Have fun.