I would go with the double ended 150 for that 12g eclipse - they are pretty deep considering and you'll need to keep the light about 6 inches above the water to keep it from heating up.
FYI - I am also selling a 7g mini bow with a power quad 96w fixture(brankd new bulb and old as spare), rock, some sps corals (green and purple tip digitata and green hydnophora) a sand bed, some snails and crabs. I also have some green striped mushrooms and purple spotted mushrooms as well. I am selling as a package for $225. If you want the yellow wathcman goby paired with the pistol shhrimp, I am asking $250. Let me know if you're interested.