What i would do is look into Build My Led. Given the fact that you have a skinny deep tank i would order one with either a 45deg. or 60deg. beam angle to insure you get that high par at the substrate. The only thing i would be worried about is if your plants grow to tall at the edges it may get no light. Also if you can order the adjustable dimmer for it to tone it back accordingly so that you won't need CO2. If you finally decide to go the high tech route you could just adjust it to full output.