This setting under Advanced Options allows you to define a default merchant account to be used for eCommerce actions. This default merchant account only applies to eCommerce transactions that are executed within Memberium. It does not control which merchant account is used for transactions that happen within Infusionsoft itself.
Learn about supported merchant accounts and payment processors used with Infusionsoft and Memberium. Learn about supported merchant accounts, 3rd party carts, and more solutions to help you sell to your membership base.