There should be a list of metals in the config allowing you to disable/enable any one of them. There's two big options on how to accomplish this:

• Have all metals the mod is able to generate in there and choose enable/disable as default based on which mod integrations are loaded
• Have a list of metals with their properties/color/name/temperature and fill this by default based on mod integrations. This would allow pack makers to add/remove liquids at will and even create new ones.