Looking for the best Cosmos Backgrounds? You will love these:

You love your aquatic pets and being able to pair them with a fascination for images of the galaxy? What could be more fun? In this article, we will take a walk through the galaxy so you can peruse the awesome line-up of images I’ve generated for you, for your cosmos aquarium backgrounds. If the perfect one for you isn’t here, you can provide your own and we will turn that into your cosmic aquarium background. It’s all good. Whatever my customers want.

The Ascetic of a Cosmos Aquarium Background

Let’s get on with it. Aquariums should be more than just a container for fish — it can be a window to other worlds. And what better way to create that feeling than with a cosmos-themed background? Whether you want to simulate the Milky Way, a purple nebula, or a galaxy swirl, these backdrops bring a sense of depth, calm, and wonder to your tank.

You’ll Look like the Aquarium Designing Professional

Having a well thought out and designed aquarium, doesn’t have to be a chore. Aquarium decor done the right way can actually be quite easy. Providing you follow a few key 2026 aquarium décor hacks, your tank can be styled up in no time. Not only that, it will keep looking great everyday.

Steps to Creating awesome Aquarium Decor

So how do we do that? I hear you asking.

Firstly, by using a background, you block the wall from showing through the front of the tank. The back cords are also covered. This keeps all distractions away, and sets the stage for the fish to be the stars.

Backgrounds help with algae, make fish feel more secure, and because the background has a design feature, little more is needed to make the tank look cool. Depending on the fish species, substrate is a good next choice. Most fish are fine with a fine sand, but be sure to research your actual fish varieties before buying your substrate.

Next step a few silk plants in crazy colours to go with your cosmic background

Final step is to stick some lcd lights to the back and you’re away.

That’s it. Your aquarium decor now looks fab. You no longer need to stress about how your tank is looking before saying yes to friends stopping by. You can be safe in the fact that it looks good. Maybe needs the magnetic cleaner run over the front glass, but that only takes seconds.

Cosmos Backgrounds: Milky Way and Andromeda Galaxy

Why Cosmic Backgrounds Are So Popular

• Visually stunning and universally appealing
• Ideal for both freshwater and saltwater tanks
• Pair well with LED lighting and colorful fish
• Easy to install and blend with rock or space-themed decor

Top 7 Cosmic Background Styles

1. Milky Way Fade
   • Deep black with streaks of starlight
   • Great for glow fish and LED tanks
2. Purple Nebula Dream
   • Swirls of purple and violet gas clouds
   • Creates an otherworldly, soft background
3. Andromeda Galaxy Field
   • Crisp whites and blues on a starry field
   • Works well in minimalist tanks

1. Cosmic Blue Gradient
   • Subtle blue fade from dark to light
   • Ideal for community tanks
2. Starlight Burst
   • Radiating effect behind decor or ruins
   • Creates dramatic focal point
3. Stellar Storm Field
   • Dynamic white streaks and movement lines
   • Great for action-themed tank
4. Meteor Swirl Backdrop

• Energetic design for fish with movement
• Great with reflective substrates

How to Choose the Right One

• Tank Size: Larger tanks can handle more contrast
• Fish Colors: Choose backdrops that contrast your fish
• Lighting Setup: Cosmic backgrounds look best with low to medium LED

Installation Tips

• Wet and clean down the back glass of your aquarium
• Static vinyl requires no adhesive, while wet secure to the top of the tank and smooth down.
• Use a plastic card to work bubbles from the middle out
• Use a Box cutter knife to trim any vinyl that may be over
• For a seamless look, use a backdrop light behind the tank

New SmartFit Sizing Option We now offer just 5 universal sizes — easy to trim to your tank at home. No more analysis paralysis. Custom sizing available too!

Ready to bring the universe into your aquarium? Get started with our cosmos backgrounds, The milky way or the Andromeda galaxy, and keep a close watch for the rest of this series of fish tank backgrounds being released over the next few weeks. Explore our Cosmic Background Collection and see all available styles, sizes, and tips.

So you don’t miss a post, why not subscribe to our newsletter. The form is just below. In your first welcome email you will get a coupon code for $10 off your first aquarium background. You’ll also be notified the minute a new background is released.

As always, thanks for reading and please make sure to share this post with someone you know, who would love a background for their aquarium.

I’m currently trying to build my Instagram Page and Following. It’s currently pretty dysmal. You can follow this link here to give me a follow on Insta. Catch ya next time. Sharon Thoms (author)