Well this is what I found. it is and SPS but as you said high sting power. I think I will move it up higher under the 400MH closer to the top. now it is under the 250W near the bottom.
Hydnophora is a highly sought after and infrequently available SPS Coral. Although colors and shapes will vary, most available pieces have a branching shape and bright green in color. Like all SPS Coral, they are difficult to maintain, but they generally not quite as delicate, or as prone to color change as Acropora sp.. They have a greater sting than other SPS Corals and should be given a little more space than other similar looking corals.
To maintain the color and health of Hydnophora it is imperative to maintain absolutely perfect water quality in an established reef aquarium, high pH, calcium and alkalinity levels, and maintain extremely low phosphate and nitrate levels. Hydnophora demands intense lighting, preferably supplied by metal halide lights, and strong, preferably intermittent water flow. Color will vary depending on the lighting conditions in your aquarium. Actinic lighting or metal halide lighting heavy in the blue spectrum will enhance their color.