Ok, the majority of reefkeepers will agree that keeping any type of live coral & some inverts require high lighting, and excellent water conditions, etc. I started with a 10gc, using the standard strip light with a 15watt Coralife 50/50. This tank had a 20-40 Wisper carbon filter as the only source of flow & filtration. I added 25 lbs of live rock, 15 lbs of live sand. I stocked the tank from the LFS's $5 tank, ie. bought 1 orange zoo, 1 small xenia, brown polyps, misc. mushrooms.
Everything survived, the zoo multiplied into 3, now have 4 xenias, mushrooms left babies, etc. My tank has a healthy growth of pink coraline too. To make up for the low lighting, the tank sat near a South window all summer & I placed the corals up high in the tank. Religious weekly RO water changes, supplementing with Kent Coral-vite.
However, now that all my livestock is in a 30gc with skimmer, proper lighting....I see a MAJOR difference & learned some lessons! While nothing died in the 10gc & even getting some babies, the corals, etc. were not thriving. The brown polyps
actually have very cool bright green centers with brown tips...never saw that green in the 10gc. The dull orange zoo's have popped & I can see them from across the room.
So, yes you can get by with minimal lighting, but your livestock won't thrive under it. I didn't get good lights for my 10 because I knew a bigger tank was only a few months away!