background sandwiched between original and replacement glass

[noodleroni]

I recently purchased a used 55 gallon tank and didnt notice until halfway home that the background is sandwiched between the original (cracked) back pane and a replacement pane sealed inside the tank. I can't remove it, I obviously can't place anything behind the tank anymore, and the background is hideous. Anybody know of an "inside the tank" background that won't leach chemicals into the water? Are there any opaque sheet materials that I could cut down and place in front of the background? A solid color wouldn't be a problem.

These gaudy corals and anemones are making my freshwater river setup look pretty cheesy. Thanks in advance for the help!

 

[Esra]

You can buy the internal 'rock wall' latex back grounds that make the back of the tank look like a cave.
They look awesome but are pretty expensive.
I'm looking for a 4x2 foot one now.