Tank vacuum cleaning system

From my link to https://permies.com/t/88043/benefits-rainfall-collection
TANK VACUUM SYSTEM
Here is a new product for North America its a Autralian product and I am not sure if its distributed in NA.
"When your tank is full, a firm namedTankVac® has developed a tank cleaning equipment that is simple to instal, powerless, and will automatically clear up sludge.
In the centre of your tank, along its floor, a unique pipe with many holes is put.
This particular pipe connects to another pipe that travels up the interior of your tank’s wall and out through the overflow.
When your rainwater tank fills up with water, it creates an equal vacuum throughout the tank’s base.
Any debris or sludge is pulled into the pipe, and the polluted water is discharged at a strong rate of up to 9 litres per second through the overflow.
The syphoning operation ends when the water level in your water tank lowers to a predetermined level.
There’s no need to be concerned about muck accumulating in your tank and needing to be cleaned out every few years. Rainwater of the greatest grade is constantly available"
https://www.tankvac.com.au/