Anubias doesn't require additional CO2 but they still require *some* CO2. The ambient CO2 level in the tank from regular water changes is ussually enough to sustain slow growing plants as long as you keep the lighting low. As always keep the surface turbulance to a minimum to prevent CO2 from escaping. You should not need to add any ferts.
Anubias are rediculously easy to keep. I haven't managed to kill one yet despite numerous successes with other species. Although they flourish in a well planted aquarium they make good solitary plants too.
Leave everything as they are. Even if you turn your tank into a whirlpool, CO2 will be at around 5 ppm. Lower surface disturbance is reccommended when you inject CO2 to raise it above ambient levels but for a non CO2 tank, the fish would do better with good surface movement.
With anubias being a slow growing, low light plant you really don't need CO2. In fact CO2 is mostly used becuase people like to see their plants grow quickly and they like to see pearling. In fact, CO2 is not necassary for any planted tank, it just makes things more interesting and easier.
But when you go to certain levels of light (say 2.5wpg, if you trust the wpg rule) then plants can become carbon limited. Good CO2 works wonders in helping plants grow and preventing algae get the upper hand.