How do I control webmail spam defaults?

Using Business Catalyst and have a number of email folders set up. One of the boxes forwards mail on to another, non-BC domain.

At that non-BC domain are many more emails than show up in the BC webmail In folder.

All BC spam control is set to 'default,' but I can't find any place that says what that default is. And I'd like to turn it off, since some of the email that BC is saying are spam are not.

I am also a domain administrator, and there is no place I can find to set systemwide email controls, parameters, or preferences. Each mailbox needs to be separately specced.