I always use the old fashioned mouth method to get the syphon going, i've got it odwn to an art form now and its just quicker but if you have trouble doing it that way then disconnect the inlet tube (the thicker one) from the canister and turn the tap to closed, then submerge the entire hose in the tank until it is completely full of water with no air bubbles. Now for the tricky bit, place your thumb over the free end of the hose (the one without the tap) and reconect the hose to the canister (it helps if someone can hold their thumb over the free end for you), then ensuring the free end is still submerged open the taps and the water should start to syphon into the canister. Once the water starts to appear in the outlet hose (thinner hose) plug the filter into the power and if all has gone well it should start running perfectly.