Renting a facility and wondering who is responsible for installing the grease trap? In the case of a multi-tenant facility with several restaurants or a food court, the landlord will be responsible unless you have a lease that says otherwise. In the case of a single tenant facility, it will depend upon your lease conditions. I am a hotel or landlord with several restaurants. Can I have one trap for all of them? Yes, if properly sized and maintained. My vendor says I can get a special additive that will keep the grease out of my system. Can I use it?
Generally these types of additives just move the grease to the sewer, where it frequently backs up right back into the facility that used the additive. Most additives are not allowed, and of the one kind that is, it has not been proven effective in grease traps. There is no magic bullet.