Hello Fishe, Rome, 123matt123, thanks for the comments, appreciate...
Rome, yes indeed. Compacting in that sense is important. Trying to leave the underground as undisturbed as possible.
The top layer of sand will still get some water over it first to settle it better. After that it's filling and testing, maybe adding some more sand in spots.
Matt, 5 to 6 Meters, not Feet...that's somewhere 15 to 20 feet wide, 30 to 35 feet long...
Plenty for Mr. T. to grow.