Step 4: Attach the Weight at the End of the Suction Tube
The number of nuts that you will need to use will be determined by the stiffness of the flexible tubing. You want there to be enough weight on the end of the tube so that when the sprayer is turned upside down, the end of the tube will hang near the level of the screw cap. Twist nuts onto the end of the flexible tubing one at a time. After adding each one, turn the sprayer upside down and check how low the end of the tube hangs. This is the minimum level of liquid that will still submerge the end of the tube when held upside down. Continue adding nuts until you are satisfied with this level. I used five nuts in my prototype.