A clear back panel shows every cable, plug and patch of wallpaper behind the tank, and it pulls the eye away from your fish. A solid black background hides all of that and makes bright fish and green plants stand out, which is why so many planted and reef-style tanks use one.

This is a roll of black film that you trim with scissors to fit the back of your tank. Clean the outside of the glass, spray it and the film generously with water (a drop of washing-up liquid helps), peel off the protective layer and lay the film on. You can slide it into position while it is wet, then push the water and bubbles out to the edges with a plastic card or scraper and leave it to dry for about half an hour.

• Plain black, cut to fit with scissors
• Goes on the outside of the back glass
• Fitted with water, so it can be repositioned while wet
• Bubbles are pushed out to the edges with a card or scraper
• Weighs 190g

On size: the roll size is not published in the listing, so we cannot confirm how large a tank it will cover in one piece. Measure the back of your tank first; if in doubt, ask us before ordering.