I believe the most common brand is taotronics. But if you search eBay or amazon for "120w dimmable reef LEDs" you'll find them. They cover 2x2 ideally, but if you wanted to hang them a little higher I imagine you could get away with 2. There is no real watts/gal
with LEDs, it's more about the power and efficiency of the individual diodes. Quality units usually run 3w LEDs, avoid units using 1w or lower LEDs as they lack the power for higher light species. The above units will allow you to keep anything you'd like though.
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