You could spend a small fortune on aquarium lighting. Or, you could drop about $40.00 on a 48 inch, four bulb fixture and $20.00 on four T8, 32 watt bulbs from the local hardware store. Just hang the fixture a foot or so above the tank. This lighting is great for a standard 55 gallon tank. The lights last many months and will grow most aquarium plants.
Your tank is 48” long so get the 48” fixture. These aquarium lights are made to fit . A great fixture to grow plants is the finnex 24/7 planted. It’s just under $200. For a cheaper copy get the aquaneet 24/7 for about $50 on eBay. Works just as well. These light fit on top of the tank and makes it look correct. Good luck .