HOW CAN I MAKE BACKROUND SHOW UP BETTER ?

The picture you get off the roll at the store. It has a nice backdrop that is not distracting but rather enhances my rockscape/sand and makes the tank look deeper from front to back than it already is. When water is in the tank it just gets dark unless water drips between the backround and the back of the tank. of course the backround goes on the outside. Is vasalene safe for acryllic or will it attack the plastic like ammonia windex will ?
 
Ah ok:) Well Bert you have to humor me I use to work at a pet store..and we had MANY a person come in asking why their background just kept falling into the middle of their tank!
 
falling into the tank ? those backrounds are for the outside back of the tank, i bet some people will try to put them inside even though they are made from paper.
 
I just want to make sure vasaline won't attack the plexiglass like windex did when the wife used it to wipe of fingerprint smudges, all these tiny cracks in the surface of the tank, good thing they were at the very top edge where they are hard to see. is there a commercial product for this ?
 
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