Hello and thank you for your message.
For your tank there are a few options that would work well. For your best solution that will allow flexible lighting options (dimming, sunrise/sunset, storm simulation, etc...) I would recommend looking at their the Ecotech Radion's or the AI Hydra's. You would need three of each of these as they will cover about a 2x2 area. The AI will also require their Controller to program the lights. For the Ecotech you can purchase their Reeflink controller if desired to sync other Ecotech equipment and easy programming. Both fixtures can be hung above the aquarium using their hanging kits.
Another possiblity is looking at the Maxspect Razor fixtures (three of the 20.5" or maybe two of the 27", but that would leave some shading on the ends of the tank). While they don't have all the features of the Ecotech or AI LED's, they are still a very good choice.
Lastly the Kessil A350W would be another great choice. Three or four of these would work great over your tank.
All of these fixtures can be hung over the tank or the Kessil sell a gooseneck holder that clamps to the rim of the tank that might work.
If there is anything else please let us know. Feel free to send an email to email@example.com or call us at 1-800-566-FISH.
Marine Depot Customer Service