QuickVac uses siphon action to remove the sand/debris that accumulate in the bottom of your tub. Just insert the suction tube into your tub, shake the tube, and the quick vac goes to work quickly removing debris and transporting it out of the tub through the discharge hose. It's amazing how much suction the siphon develops. Removes glass, pebbles, sand, and leaves. The QuickVac discharge hose is 8-feet long and drains about one-gallon per minute. Spot clean in as little as 3 or 4 minutes.