I need a new background for my 20 gal high tank. One I've had for a long time isn't sticking as well and is cracked some. I had used vaseline when I put it on before. What would be the best way to stick it to the glass without just using tape around the edges. I want the image to pop. I read elsewhere you can use water. If I use the water method, do I need to spray just the tank or the tank and background? Also read something about using liquid soap or something like that too. Thanks in advance.