I run 2 18 inch fixtures over a 20 inch cube tank. I'll just give a few thoughts.You can grow anything you want with this light. The blue and red leds dont appear bright to us but produce a ton of par. Plus they have a sort of high def. look to them, very hard to explain. I had 2 finnex ray2 before the BML lights. The ray2 gave me about 50-60par at the substrate but looked really bright. With the BML lights I can get 100+ par on the substrate at 100% (this is with the regular version, not xb) but it still doesn't look as bright as the finnex lights. I found that one fixture is probably only good for 12 to 15 inches front to back if only a few inches above the tank. However, if you go for the xb version and hang it high enough you could use one and still have plenty of par. In fact it would probably still need to be dimmed . As far as light automation, BML is coming out with their own soon. Besides them you would need a reefkeeper or apex which is pretty pricey.