The Basics of Marine Aquarium Backgrounds

Paint and commercially manufactured sheets are two common types of backgrounds

Paint and commercially manufactured sheets are two common types of backgrounds

When setting up a new saltwater aquarium, one of the many decisions you’ll need to make is whether you want to put a background on the tank and, if so, what kind you’d prefer to use.

The choice of background may seem like an insignificant concern when your mind is swirling with all sorts of equipment and livestock decisions, but don’t sell it short. A background—or lack thereof—can make a big difference in your aquarium’s aesthetic appeal. Not to mention, it won’t be so easy to add or change a background once the system is up and running, so which type of background to use (or not) is a choice you’ll need to make sooner rather than later.

Benefits of a background

An aquarium background can offer a variety of potential benefits, including:

  • Concealing cords, hoses, and tubes running down the back of the tank
  • Increasing the perception of visual depth—i.e., creating the sense that the aquascape extends beyond the glass or acrylic walls of the tank
  • Giving fish a greater sense of security
  • Either enhancing the naturalistic beauty of the aquascape or introducing a touch of whimsy

When a background isn’t your best bet

Obviously, there are situations in which putting a background on an aquarium would be counterproductive—for example if you’re using the aquarium as a room divider and want to be able to view it from both sides or, similarly, if the tank is installed in a wall between two rooms and is, thus, viewable in each room.

What type of background suits you?

Your options for a background are quite varied and can range from exceedingly simple to relatively complicated, depending on your preference. They include:


Simply painting the outside back pane of the aquarium is among the most common choices, and black and various shades of blue are the most commonly used colors. I’ve used flat black latex paint on the back of several glass aquariums with very satisfactory results. I prefer to roll it on the back with a small paint roller to avoid leaving visible brush strokes.

Be sure to clean the pane very thoroughly so there are no oily spots, fingerprints, etc. to interfere with the paint’s adhesion. Also, make sure each coat dries thoroughly before attempting to apply another coat. Latex paint will peel off glass very easily if it’s not completely dry.

Plastic sheeting

If you want a less permanent approach than paint, you can simply affix a sheet of black or blue plastic to the outside back of the tank. I once even used a cheap plastic trash bag to temporarily cover the back and sides of a quarantine tank. Believe it or not, it actually didn’t look as awful as it sounds.

Self-adhesive backgrounds

A step up from plastic sheeting is using a commercially manufactured self-adhesive background. These are available in various dimensions to fit different tank sizes and come in all kinds of designs, from solid colors, to photographic coral reef images, to just about any other design your mind can conjure up—some downright strange, frankly.

3D dioramas

Three-dimensional diorama-style aquarium backgrounds can add a really impressive, naturalistic flair to a marine system. If you have the DIY knack, you can craft such a background yourself from various inert, saltwater-safe materials, or you can purchase a ready-made, commercially manufactured insert.

If you choose to go this route, keep in mind that this type of background can present certain challenges. For instance, if there isn’t a tight fit between the background and the inside of the tank, it might be possible for fish to slip in behind the background where they will be very difficult, if not impossible to catch. Also, cleaning such backgrounds may prove to be difficult, and some DIY materials may not hold up to constant picking and grazing by aquarium livestock.

No background

Of course, you always have the option of using no background at all initially and just allowing coralline algae to coat the back—and possibly the sides—of the tank over time. Do keep in mind, however, that a thick coating of coralline, while attractive, can be tough to clean off if you should eventually decide to do so.

What’s your background?
If you’ve done something creative or unique for your marine aquarium background, please share it with your fellow salties in the comment section below.


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About Jeff Kurtz

Jeff Kurtz is the Co-founder/Editor of Saltwater Smarts, former Senior Consulting Editor for Tropical Fish Hobbyist Magazine, and the aquarist formerly known as “The Salt Creep.” He has been an aquarium hobbyist for over 30 years and is an avid scuba diver.


  1. I am have black mat textured shelving liner from Walmart taped on the back of most of my tanks.

    Just cut and tape.

  2. I have 4 tanks and the only background I don’t care for is the plastic sheeting one as no matter how smooth and ‘attached’ you get it in the beginning eventually they start to bubble up and look bad. Recently set up a new tank and we sprayed the back with an awesome blue. Best looking background ever! Highly reccomend!

    • Bubbling is definitely a common complaint with plastic sheeting. I’m with you when it comes to painting the back. It’s really easy, even for someone who’s all thumbs like me, and I’ve always been pleased with the results.

  3. I just painted my 90g reef tank with black Plasti Dip (a flat black, rubberized spray paint that’s easily removable yet very durable). It looks amazing. My best background ever. Going to do my sides next. 2 cans and $12 later from Lowes and I’m all set. (Took about 4 coats)

    • Chris Aldrich says

      Plasti Dip is a great idea, Steve. I’ve used it for automotive applications numerous times and it didn’t even occur to me that it would work fantastic for an aquarium background, as well. Thanks for sharing!

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