if you're painting the back of your tank, you can just your regular old black, (matted finish) spray paint. it's probably gonna take you a few cans of paint just for the back. even when you think you've covered all the spots, and the whole entire back looks solidly black, light will still shine through on a few spots. you really have to get several nice coats on there. use a light to check it.
as for the stand, wood has a tendency to absorb the paint, so slap a coat or two of primer on there, and then just paint it. if you want it glossy, then use a high and/or semi gloss paint, or matted if you like.