They are both hard to keep. The orange is only "relatively" easier to keep, but that is relative to the blue....not that it is easy or hardy to keep. Both need a large mature reef tank with pristine water conditions. Neither can be spot fed. The blue is larger, and therefor needs a lot more LR. But I personally wouldn't try an orange with anything less than 100lbs of LR in a 75g reef tank, and that is definitely no guarantee of success (which is measured at the 18 month point).