I used a black garbage bag since it's only a temp grow out tank and didn't want my gar to have a glass crash.
I did 3 out of 4 sides so he knows his travel distance.
I painted my two tanks with acrylic paint at the weekend and not really sure about it yet. The fish might pop a bit better than against a light background but with the black you can see every mark, scratch and bit of dirt. One of the tank is showing a whole load of my shell things which I'm not sure what they are
Here's a few pics, the tanks are a work in progress at the minute. Going to get them sorted this weekend so will stick up more pics then.
Spent a day painting them. Used three coats and left them dry for about 2 or 3 hours inbetween.