Painting the back of the tank

[Vagabond]

Found this on RC sounds interesting so I think I will give it a try and post my results:

SIMPLE SOLUTION: VINYL

"I got a piece of black vinyl, though you can get blue or other colors. You can get it from any sign shop, or from automotive lettering folks. It's not very expensive.

You peel off the backing, and that side of the vinyl is adhesive. You take a water bottle mixed with a little Joy dish liquid and spray liberally on the sticky side. Then apply to the tank, using a squeegee, credit card, etc. to push the water bubbles to the edges. The water bubbles move very easily, as opposed to air bubbles which don't, so that's why you do it this way. Voila.

No water will get between it and the glass. It won't fall off. It won't scratch. It looks awesome. It's not toxic. You can remove it in 2 minutes, and you're tank is still perfect.

What's real cool is when it dries, there will be a slightly chalky appearance - this is from the dishliquid. I freaked, and called my friend who does sign work and yelled at him. He told me in a couple days, the chalk will literally disappear. I thought he was full of it, but it did. Completely gone.

Anyway, it's a very simple process, no worries about air bubbles or anything like that".