Tank Duration Calculator

The most sobering math on the fireground: how long your booster tank actually lasts at your current flow. Count the seconds before your supply line matters.

Tank water (gallons)

Total flow (GPM)

All flowing lines combined.

Hose fill (optional)

Charging an empty lay eats tank water before a drop reaches the nozzle. Enter the lay to subtract it — or leave the length blank to skip.

Hose diameter (in)

Hose length (ft)

Enter values above to see the result.

Watch it for real: flow a line from tank on the pump panel and watch the level drain. Open the pump panel