Those bulbs are normal output fluorescent bulbs so whether or not you can keep corals depends on how many bulbs you can cram over the tank and what kind of corals you want to keep. Unfortunately, I would say that (unless you are overdriving them with an
Ice Cap ballast) even if you had 6 bulbs over the tank, you would likely be limited to mushrooms, polyps, and maybe some
soft corals. A 55 gal tank is relatively deep and normal output bulbs don't really have enough power to penetrate the water well.
