How wide? Any idea what you are going to keep? Do you have a penchant for tinkering, or do you just need something to plug in and let it rip?
There are all kinds of choices from 2 or 4 bulb T5, cheaper Chinese black box LED, slightly more expensive LED like ReefBreeders or SB Reef lights with more channels and stuff, LED strips... all the way to expensive LED that might cost several thousand of dollars that come with wifi apps and stuff. The T5s will do a great job and you just plug them in. The LEDs get more expensive as you choose features, channels and coverage.
Don't sweat energy efficiency - there is no efficiency between light types, just choices. If you NEED 100w of T5, then you will need 100w of LED too...and vice versa. If you CHOOSE 400w of LED and only ended up needing 100w of T5, then it was not the lights that were bad, it was the choice and it does not mean that LED are less efficient than T5s.
This is a good watch for a lighting first timer... just facts to help with your baseline understanding: