attach... make sure everything is tight.... put it in the open position. and the think by the sink all the way down... turn on the cold water... the more water pressure from the sink the harder it sucks.... then put it in your tank and suck the desired amount while cleaning your gravel....
then let your hot water run and get the right temp... go close the thingy by the gravel tube.... once the temp is good move the thingy up and to the left... run to your gravel tube, but it in the tank and turn it open... the water will start to flow.
add your dechlor slowly drop by drop... then close it, run to your sink and turn off the water.... and release the thingy into the drain position.... your done
dont leave it closed with pressure coming to the gravel tube