also, let me share the experience I have with this type of light with you.
It will generate a tremendous amount of heat both in the room where the tank is in and in the water. Your tank will have an increase of at least 3degrees when MHs get turned on. And that's when MHs are 9in away from the water surface. Yours is about the plastic legs ht, so that's about 4" about the water, plus looks like you have the glass top covering the tank. That will cause some serious evap. on the glass tops, salt buildup, and serious temp. increase. I lifted mine up that high and still not enuf. I had to add a full size 21" floor fan blowing at the tank, and you know what, my tank still has 2degrees water temp change and 7 degrees temp difference btw my bedroom (where the tank is) and every other room everyday.
So, get ready.