Proper Ground for Tonearm and Turntable

The tonearm is the only thing that should be grounded to the phono stage. If you must ground the plinth, it should be to your building ground (usually the cold water pipe coming in from the municipal water supply, only if it’s metallic) through a dedicated ground lead. If you use a well, the building ground electrode should be a long copper rod driven into the soil close to the foundation - check your local electrical code requirements for more info. 

Mijostyn you are very wrong on all counts. First and foremost, the tonearm requires a signal ground from the phono stage, and if you tie it to the plinth, you have just created a ground loop. Second, the phono stage needs to be grounded to the pre-amp / integrated amp. On an integrated amp, many manufacturers tie the common negative speaker leads to chassis ground. The OP was wise to consult the manufacturer on this, although the same result could probably have been achieved by grounding the phono stage chassis to a chassis screw on the preamp or integrated amp. Third, the Zerostat is a well-proven device to neutralize static buildup. A grounded sweep arm is not necessary, and in most cases it will do no good. 

Everyone knows that Zerostat is the first step to clean vinyl signal reproduction. If you weren’t drunk, you would realize that the “ground sweep arm” as you refer to, only neutralizes static charge that exists in the groove *before* the stylus, and is thus ineffective at neutralizing static charges caused by the friction of the stylus. Please get your facts straight.