It takes 42.5w sq/ft of the very best LED Diodes to equal the best HID Single Ended. 1000w Hortilux HPS has the highest umol of any SE HID. 1600umol
The very best of the best LED Diodes to my knowledge are the Samsung 301h,,,,,, and Osram
The Gavita 1700e is 645w at the wall. And 1700umol, and is made specifically to replace a SE HID in a 4 x 4 area as per Gavita. There are a couple lights that are just a bit more efficient, but not by much. The Phillips Greenpower is the best, but they dont sell individually. They are 635w, and 1800 umol. They will sell 40 of them for $32,000, which is a steal at $800 each.
But going by Gavita, for optimum growth through the full cycle, one needs 42.5w sq/ft
The LED you have is very inefficient. Id put it no more than 15 inches from canopy.
Many LED manufacturers are guilty of highly overrating their products, and also use misleading advertising like say using 1000w in the ad, when the actual watts are 180w, and 1000w has nothing to do about anything involving the light.
Bottom line as was stated above, draw at the wall, and the type of Diodes, and Drivers used is what matters.