5 Cool Fish Tank Themes You’ll Want to Replicate

Shooting for the stars? Then landing on this space-themed tank just might be the inspo you’ve been looking for all along. It features an astronaut and a glowing planet, plants, rocks, and gravel.

“When I decided to get a fish tank, I knew it had to be space-themed,” says Casey Denham, aerospace engineering student at Virginia Tech in Hampton, Virginia. “I really wanted it to be deep space and exploration themed, so I went with glow decorations.”

Best advice for taking on a tank theme that’s like nothing on Earth?

“Look for items that will look good when they glow together. The purple and blue look well, but the orange provides a good contrast,” Denham says.

If “SpongeBob Squarepants” was (or still is!) one of your favorite TV shows, then why not bring Bikini Bottom to your very own home? Well, your fish’s home, that is.

Allyson Piangenti, a fish tank owner living in Middletown, Connecticut, says she saw the Bikini Bottom fish tank décor years ago and always thought it would be fun to put together.

“I finally went ahead and did it [and] it was pretty easy,” Piangenti says. “I used all artificial plants, figurines by Penn-Plax and natural aquarium sand that was safe for both freshwater and saltwater tanks … I also found a picture [of a Bikini Bottom backdrop] on Google and had it printed and laminated for the background.”

“Finding Nemo” and “Finding Dory” are movies that have fish as main characters, so a tank in honor of both movies just makes sense.

To create a tank similar to this, you’ll need a coral background or artificial coral accessories, brightly colored pebbles, Disney stickers and aquatic ornaments of Nemo, Dory, Hank and any other of your favorite characters from the movies.

Is creating a zen-like environment in your home important to you? Create a tank that’s equally as relaxing to look at as it is for your fish to swim inside.

To design a tranquil tank, add in some stone caves, a Buddha, ancient-looking architectural ornaments and some live plants, like the moss balls that are in this setup.

“Make sure your fish’s needs are your priority,” explains Florence Gosselin, a fish owner living in Montréal, Québec. You can buy fish tank decorations that are pleasing to the eye, but more importantly, that create a healthy living environment for the fish inside, says Gosselin.

You can even add a bubbler, like the Aqueon Flexible LED Aquarium Bubble Wand, which is calming to look at and, even better, helps circulate the oxygen in the tank.

When in doubt, glow your fish tank out! This easy-to-execute fish tank theme is sure to make a bold statement in any room.

“It was easy to create,” says Lauren Rawlins, the fish tank’s owner who lives in Washington, D.C.

Rawlins says she used all of the items that came from a 20-gallon GloFish starter kit as well as a jellyfish, glow-in-the dark plant and gravel, and a light-up volcano bubbler to make this glow tank come to life. She also added in some live plants to give the fish a place to hide.

Here, we explored five fish tank theme ideas: an Outer Space fish tank, a SpongeBob-inspired Bikini Bottom tank, a Finding Nemo and Finding Dory aquarium, an underwater zen vibe, and a glow-in-the-dark decorated fish tank. 

Start by choosing the look and color scheme you want, then choose fish decorations that work for your aquarium size, while also keeping your fish’s needs a priority. Next, choose your substrate (gravel or sand, for example, a background (if desired), and then top it with live or artificial plants, caves and bubblers, ornaments, driftwood, etc. to create your desired fish tank theme. 

Choose live or artificial plants depending on your aquarium type and set up. All of your fish tank theme ideas and how you implement them should consider your aquarium size, number of fish, maintenance and cleaning routine, and whether you have a saltwater or freshwater aquarium. Whether live or artificial, plants make great places for your fish to hide.