Right now I am using a ReefBreeder 24 Photon V-2+ and my tank is also 30" across, which is the same as your 20 gallon Long. It might be more investment than you are wanting now. It's what I would describe as the more reasonably priced of the nicer LEDs. It has 6 different colors so you can tailor it for whatever you have.Ok great I will hold off then, I was on the fence about it bc of the macro. What light do you think I should get for the tank- should it be geared more towards plants or marine? I may have a couple of coral eventually so I’m not sure what light spectrum to use that will grow both coral and macro