reef tank background

I have always been dissatisfied with the color of my Fluval M90s back wall. It looks to me like schedule 80 Gray but dull. I was thinking of cutting a piece of black acrylic to the same dimensions and cover it. Perhaps glue it to the existing or maybe just some nylon nuts and bolts or clamps...

Here’s what the room and reef tank look like after the main lights over the reef turn off. This is just before all of the lights in the room turn off for the night…