One of Hydra 52 or 30x, will likely not be enough for more light demanding corals around the perimeter of the 36", but what I would likely do.
If you go with two of either you get more even light throughout, which might not necessarily be a better thing, and if you do go 2 of then go smaller, hydra 26 or 15x
Bigger hydra or radion gives you deeper penetration. So deeper tank you need deeper penetration. Radion or hydra do about 24" spread. They claim they can do up to 36" but then you'd have to raise the light to increase the spread, lowering overall intensity.