When I inherited my tank 5 years ago it only had a malfunctioning dual fluorescent strip light where 1 of the bulbs intermittantly came off and on (that is 30-60 watts on a 45). I went ahead and got 50 lbs of live rock and cycled the tank intending on upgrading the lights. Finanaces changed and that didn't happen for 3 years. In that time, there was really nice coralline growth on the rocks. It was mainly a deep maroon and some lighter pinky purple. The original mixture that included orange and green faded to the maroon and has since turned back green since upgrading my lights to pc. There was heavy enough growth I had to regularly scrape it off the front glass.
The point is, yes you can grow some great coralline with minimal lighting, but realize it will 1)be a FOWLER set-up unless you are motivated enough to try a deep-sea habitat where you have non-photosynthetic organisms and 2)if you upgrade lighting later once you have coralline acclimated to low-light, then you will go through a long adjustment period with some bleaching of existing rock and a possible visual change of the surviving coralline.