While I'm sure you're just trying to help, I would recommend that nobody follow the above table, as there are way too many variables to have a "rule of thumb" for header size vs. length, especially if we're talking about putting a tank over them.
Not to mention a Fully Studded Load Bearing wall requires NO Header . The force is pushed down equally on all studs with or without a header. If there is were a opening in the wall a header with Proper king and Jack studs would be required.. . When i build load bearing walls in basement I will used bridging and sometimes strapping or sheathing but almost never a Header