MH Ballast mounting

Would it be alright if I mounted my 2 250w electronic MH ballasts directly to the back of my stand?

 

Is it a wood stand or acrylic?

If its wood you should be fine structurally to mount it. Be thoughtful where you do. I had a 250w double ballast mounted on the back of my stand. One of my power heads decided it didn't like being stuck to my glass anymore, turned upside down and sent water down the back of my tank and into my ballast! This was mounted inside the cabinet but the water just hugged the wood and came right in a slot in the back.

 

Its wood. And i have 2 single 250w ballasts. Where would you recommend putting them?

 

A vertical mount is usually preferable to mounting on the "floor" of the stand. There is no single perfect answer to "where to mount," but factors such as available surfaces on which to mount; space between sump and rear wall, drilled or overflow box, and other variables add to the mix.

Consider air movement in the underside of your stand. Also consider potential leakage points. Is water apt to splash on vertical surfaces under your tank, or is spilling on the horizontal floor of the stand more likely?

 

I would first consider fire hazard.
Good building supplies could include aluminum sheets and fastening parts from home depot