Tank Tender is an extremely accurate gauge system that uses air pressure to measure the liquid level in a tank — without using electricity! As such, it is an highly reliable system that will continue to function even if your electrical system is down.

The Tank Tender system is very simple. Just select a tank, then pump in a small amount of air to obtain the tank level in inches. A calibration card allows you to convert from inches to gallons, if desired.
Only precision valves, pumps, and easy-to-install push-in connections are used. The "sensor" is just a thin plastic tube, with no electronics or moving parts - the ultimate in simplicity and reliability. Connection from the tank to the panel is via thin 1/8" OD flexible nylon tubing.

• Use for water, diesel or holding tanks (not for use with gasoline)
• Monitor the levels in all your tanks with just one unit
• Individual sensors and valves eliminate the possibility of cross-contamination among tanks. Fluid is never removed from any tank; only a few bubles of air are pumped in
• Panels are available in 4-, 5- and 10-tank models, with scales for deep or shallow tanks (up to 30" water/35" diesel, or 60" water/70" diesel). The models for a maximum of 4-tanks are shown here
• Panel dimensions: 4"W x 6"H x 2-7/8"D
• Panel cut-out dimensions: 3-1/16"W x 5"H
• Although capable of measuring several tanks, the most basic panel comes with just a single selector valve on the back for measuring a single tank; with the option to add additional tanks at a later time. See below

For measuring Holding Tank levels, panels with an optional Purge Valve are available. The Purge Valve allows temporarily bypassing the panel gauge to exert maximum air flow through the tank sensing tube, clearing any material that may have lodged in the tip of the tube and ensuring an accurate reading. If you know you are going to include a holding tank in your system, we strongly recommend purchasing a panel with a Purge Valve.