I'm very much a newbie, and one very confused one at the moment. I have my first shipment of plants coming in and I think my single 18w T8 5200k bulb is not going to cut it. (tank depth is 18")\n\nI'm looking at these two fixtures currently:\nhttps:\/\/www.marineandreef.com\/Aqueon_OptiBright_Plus_LED_Fixture_30_36_inches_p\/res15721.htm\nand\nLifegard Aquatics 30" Ultra-Slim Plant LED Light (Lifegard Part No. R800058)\n\nI don't know if either is any good, if one would do, or if I'd need two for my tank. Would I be better off with something else?