All vertical tanks larger than 125 gallons water capacity have additional requirements as specified in sections 6.8.6.3, 6.8.6.4, and 6.8.6.5 in the LP-Gas Code, 2024 edition, these are not new requirements. You also need to see section 5.2.4.4 for details on these requirements. The requirements summary is that these tanks must:

1. Be installed on reinforced concrete or steel structural supports according to 5.2.4.4, which requires:
   1. Self supporting without guy wires,
   2. Designed to withstand wind loads at the site,
   3. Designed to withstand seismic loads at the site,
   4. Designed to withstand hydrostatic test loads the tank may be subjected to, and
   5. Wind and seismic loading shall be in accordance with ASCE 7, Minimum Design Loads for Buildings and Other Structures.
2. Steel supports shall be protected against fire exposure,
3. Vertical and horizontal tanks in liquid service shall not be manifolded together, and
4. Vertical tanks of different dimensions shall not be manifolded together.

See the sections listed for the details.