Heating Help

Securing Oil Tanks to prevent floating away

With this recent storm I saw several oil tanks that floated to new locations.  My own oil tanks (2) located outside  floated up then tipped over but I didn't suffer any leakage.
On FEMA's website they show to secure the tanks with straps and rods in the ground but I've never seen them at heating supply stores.

Do you gents have any ideas how to secure oil tanks to prevent tipping or floating away in a flood condition?

strapping them down

This has been law here on my part of Cape Cod for decades, when near tidal or flood zones. It most definitely needs to be on a concrete slab or floor, I use strike anchors, cable and nippers, 2 straps per tank. They go nowhere. These I buy from a local lumber supply yard that sells about everything