5 Mini Fish Tank Ideas You Can Set Up Anywhere

Thinking about setting up a tiny aquarium for your room or desk? These 5 mini fish tank ideas are perfect if you’re just going for decoration.

Just a quick heads-up—these tanks are mostly for looks. Anything smaller than 5 gallons is not a good home for fish or other living creatures.

Even a betta fish needs at least 10 gallons to live comfortably. So treat these setups as fun decor, not a real habitat.

5 Mini Fish Tank Ideas

1. Mason Jar Mini Tank

This is one of the easiest mini aquarium decorations you can make. All you need is a wide-mouth mason jar (about 1 liter or bigger).

How to make it:

1. Rinse and dry the jar properly.
2. Add a layer of colored gravel or small pebbles at the bottom.
3. Place a tiny ornament like a castle, treasure chest, or pirate skull.
4. Drop in a few plastic plants or fake moss.
5. Add glass marbles or stones to fill any empty spots.
6. Fill with water if you want the underwater effect. Optional.

Set it on a shelf, side table, or work desk. No filter needed—this one’s for looks only.

2. Mini Bowl Terrarium

This one looks like a fishbowl but works like a dry terrarium. Use a classic small fishbowl (1–2 gallons) or a clear salad bowl.

How to make it:

1. Add a thin layer of sand or light-colored gravel at the bottom.
2. Stick in small plastic plants, driftwood, and seashells.
3. You can place a tiny plastic fish or sea turtle figure to complete the look.
4. Don’t add water—this one’s purely decorative and super low effort.

Looks great on side tables, bookshelves, or bathroom counters.

3. LED Cube Display Tank

This idea is perfect if you want something that glows. You’ll need a small clear acrylic cube (can be found at craft or home stores).

How to make it:

1. Wrap LED string lights around the base or tuck them under the cube.
2. Add a few transparent stones or gems inside the cube.
3. Place fake coral or glow-in-the-dark pebbles to give it that underwater vibe.
4. Keep the lights battery-operated for easy placement anywhere.

It makes a great night light and a cool decor piece for modern rooms.

Want the inside track on Aquascaping Inspirations? This post is your go-to guide. 10 Betta Fish Tank Aquascapes Ideas So Beautiful, You’ll Forget They’re Just Aquariums

4. Teacup Aquarium Decor

This one’s quirky and perfect if you like vintage or cute setups. Use a large teacup or soup bowl with a wide mouth.

How to make it:

1. Fill the bottom with blue marbles to mimic water.
2. Add a mini diver or rubber duck figure.
3. Use tiny plastic plants or artificial seaweed around the edges.
4. If you want to add water, just keep it half full for the splash effect. But no real animals.

Great for desks, vanity tables, or windowsills.

5. Wall-Mounted Fake Tank

Want something that doesn’t even take up table space? This one goes on your wall like art.

How to make it:

1. Get a shallow shadow box frame or a deep wall shelf with a back panel.
2. Add a printed aquarium background to the back of the box.
3. Arrange fake aquarium plants, coral, or plastic fish inside using glue or double-sided tape.
4. You can even add a clear acrylic front if you want the glass tank look.

It looks super realistic and works well in hallways or entry areas.