I have heard that the easiest way to turn your background black is to paint the exterior, is this a common practice? and what are the steps in doing so? Thanks
i'm not sure it's the easiest way. it might be the most effective and attractive. i went to my lfs and purchased a black background. they sell the type that has two-sides, one black and one blue.
Rustoleum or Krylon water based gloss black paint. You will be done in one hour max.
Wipe the outside face of the back pane with alcohol and paper towel. Wipe them again with water and paper towel and spray away. You're lucky if you have a uniform looking paint from the outside. There is bound to be thicker spots that will drip specially if you are doing the edges. Although it wouldn't show when you are looking at the tank. The beauty with black paint is that it hides the uniform paint job (if there is one) very well.
Latex paint is what I have used. It peels off super easy if I ever decide to remove it. I can also apply it inside (moving a tank outside to spray paint it is a PITA)
I just painted the back of my 30 gallon last night with rustoleum flat water based latex paint, and it looks great. Just put a thin coat first, and let it fully dry, then go over it again, and let it dry. Just keep doing this until it is fully covered. It took me about 2 hours total.