The best way to convince you that it is really possible to clean a tank within 1 minute is by showing you. Compare this 1 minute to a normal cycletime of a tank washing machine (usually between 15-60 minutes).  But actually we are very proud to show the test result.
The dimensions of the tank are l x w x h = 3.5 x 2.5 x 3.75 m. On purpose the spray head of the machine was hanging at half heigth in a corner of the tank, to simulate the behaviour of a quadrupled tank of 7 x 5 x 3.75 m.
The video pictures show the back-top corner of the tank. After the top surface pollution has been pushed in the corner systematically (51 seconds), the rest is washed down very rapidly.