id say yes just cos people like it, i tried it with black card and didnt liike it at all, but it does make your decor stand out a little better also, it is all about personal opinion....................
I've never been brave enough to do this with my bowfront as I definitely don't want to end up ruining it in any way. Same thing with the concrete diy backgrounds.
There are ways to attach the pet store backgrounds to your tank that make them look good. I've seen tanks that have used vaseline to press the background up against the tank and it looks really sharp. Just have to press out the air bubbles and such. It can be messy and is best done before the tank is full. But still cool.
I would like to try a hand at painting one of my piranha tanks with a black backgroud but dont want to risk wrecking it... I use these dynamic backgrounds from Jewel in my tanks, there look great and are brilliant quality. There quite expensive but well worth the money in my opinion...also they come in two different size formats, at fit perfectly in Jewel tanks.