For a mixed reef, you can get 48" of coverage. If you want sps growing on the wall, you would need a second one then. I have been happy with my used one and my new one. I ran 1 ap700 over my 54" x 30" for 1.5 years before I added the second one.
AP700 | Kessil LED Lights
Advanced LED grow light, plant light, aquarium light solutions for horticulture and aquarium applications - AP700
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