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Home > Fish > 11 DIY Aquarium Decor Plans You Can Make Today (With Pictures)

11 DIY Aquarium Decor Plans You Can Make Today (With Pictures)

variety of fish inside a decorated aquarium

If you’ve ever set up an aquarium before, you likely know just how expensive aquarium decorations can get. Even for a small tank, you may spend upwards of $50 to get your tank set up just how you envisioned it.

DIY aquarium decorations are a fantastic way to save yourself some money and create one of a kind décor that suits your tastes perfectly. Sometimes, you may even be able to use extra supplies you already have lying around the house, saving yourself even more money and avoiding a trip to the store. Here are some of our favorite free DIY plans for creating unique and affordable aquarium decorations.


The 11 Plans for Building Your Own Aquarium Decorations

1. DIY Aquarium Tunnels by Rad Linc Crafts

DIY Aquarium Tunnels
Image Credit: Rad Linc Crafts
Materials: PVC pipe, aquarium rocks
Tools: Aquarium-safe glue
Difficulty: Beginner

This simple DIY aquarium tunnel plan will have your tank filled with tunnels in no time. You can cut PVC pipes to fit your space, but pre-cut pieces like Y-connectors are best because they don’t contain sharp edges. If you decide to cut your own PVC, make sure to sand any edges until smooth.

With just three items, you can have aquarium tunnels in your tank by this afternoon. Make sure to select an aquarium-safe glue or silicone for this project.

2. Aquarium Stone Terrace Cave by PetDIYs

DIY Aquarium Stone Terrace Cave
Image Credit: PetDIYs
Materials: Air dry clay, silicone rubber, wood pieces, plastic sheet, cement
Tools: Nails, hammer
Difficulty: Moderate to hard

This stone terrace plan is a little more complex and does require some knowledge of working with cement. You’ll simply use air-dry clay to create a terrace cave to fit your tank. Once the clay has dried, you’ll use silicone rubber to cover the clay, which will then create a silicone mold.

Once the mold is made, you’ll have to carefully work through filling the mold with cement. Avoid contact with wet cement with skin as it can cause injuries. Once you’ve created your molded terrace cave, it’s time to kick up your feet and wait. It’s recommended to let this item sit for around a month before adding it to your tank.

3. DIY Slate Terrace by Diiz iz Re4L

Materials: Slate or other flat, aquarium-safe rock, river rocks
Tools: Aquarium-safe glue or silicone
Difficulty: Beginner

This stacked slate décor is incredibly easy to make and can be ready to roll in a matter of hours. Slate is the recommended stone for this project, but you can use any flat, aquarium-safe rock that you have on hand. Make sure to sand down any sharp edges on the stone to prevent injuries to your fish.

Aquarium silicone may be the best adhesive for this project since you’ll be adhering rocks together, but some aquarium-safe glues can be used as well. Make sure to allow the glue to fully cure before adding this to your tank.

4. DIY Aquarium Planter by

DIY Aquarium Planter
Image Credit: PlantedTank
Materials: 2-litter soda bottle, rooted plants, substrate, rocks (optional)
Tools: Box cutter, drill, aquarium-safe glue
Difficulty: Moderate

This DIY aquarium planter is a fantastic way to anchor your plants in a bare bottom tank, as well as to keep your plants in place if you keep fish that like to dig in the substrate and uproot plants (we’re looking at you, goldfish).

You’ll only need a few simple items you likely already have around your house to create this planter. You can add weight to the base of it to help keep it in place. If you’re not crazy about the idea of a 2-liter soda bottle blatantly hanging out in your tank, you can use aquarium-safe glue to attach rocks and moss to the outside of the planter, allowing you to easily disguise it.

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5. Styrofoam Aquarium Background and Faux Roots by Kevin Wilson

Materials: Foam boards, spray foam, aquarium-safe paints
Tools: Aquarium-safe glue
Difficulty: Moderate

The cool thing about using Styrofoam boards and spray foam to create aquarium decorations is that you can make something incredibly unique and natural-looking. This Styrofoam aquarium background is a great way to add texture and a unique look to your tank without breaking the bank.

This project does require some knowledge of working with spray foam, so there may be a learning curve if you are new to this medium. Make sure to verify that any products you’re working with are aquarium safe. Some paints, foams, and adhesives contain ingredients that can be deadly for your fish.

6. Floating Aquarium Island by Aquatic Art

DIY Floating Aquarium Island
Image Credit: Aquatic Art
Materials: Fishing line, Seiryu or volcanic rocks, moss, grate, dowels
Tools: Aquarium-safe glue
Difficulty: Moderate

This floating aquarium island looks way more complicated to achieve than it actually is, and it will have everyone wondering how you did it. You’ll need a handful of supplies, but this project shouldn’t take you too long to create.

Securing the fishing line to the rocks can be difficult, so use glue or silicone as needed for security. You don’t want rocks dropping onto the bottom of your glass tank. Choose mosses or other plants that will happily grow attached to rocks and you’ll have floating islands in your tank in no time.

7. Custom Aquarium Background by Dramatic Aquascapes

DIY Custom Aquarium Background
Image Credit: Dramatic Aquascapes
Materials: Styrofoam, colored cement
Tools: Aquarium-safe silicone, rubbing alcohol
Difficulty: Moderate to hard

Once again, we’ve come to a project that isn’t overly complex, but it does take some level of comfort working with cement. This DIY aquarium background consists of Styrofoam that has been shaped to look like rocks, which is then covered with colored cement.

You can really kind of go crazy with this project, though. You can make your tank’s background look however you want it to look, and by using colored concrete, you have more options than you would buying a premade background.

8. Painted Aquarium by PetDIYs

DIY Painted Aquarium
Image Credit: PetDIYs
Materials: Wet erase markers, black fabric paint, glass paint
Tools: None
Difficulty: Beginner to hard

If you’re looking for the perfect way to express yourself with your aquarium, look no further than this painted aquarium DIY. You will be able to create your own completely unique designs outside your tank. Wet erase markers allow you to draw out your design and make changes before finalizing everything.

Glass paints will permanently change the appearance of your tank, so make sure you are fully settled on your design before you begin painting. Make sure to keep the marker and paints on the outside of the tank, as many of these products are not aquarium-safe for use within the aquarium.

9. 3D Aquarium Background by Instructables

DIY 3D Aquarium Background
Image Credit: Instructables
Materials: Foam insulation, additive-free silicone, bamboo skewers, toothpicks, hydraulic cement, liquid cement pigments
Tools: Serrated knife, paintbrushes, drop cloth, tape measure, pen, wire cutters
Difficulty: Moderate

A 3D foam background for a freshwater aquarium lets you explore your creativity, giving you a blank canvas to make any design you desire. It only takes a serrated knife to trim away a rocky background custom fit to your tank. Skewers lend support to protruding sections so you can give your fish more features to enjoy.

Building and dry-fitting the background to fit your tank is time-consuming but fun. The most challenging part comes in applying the multiple layers of cement. It’s extremely messy, and each coat takes several hours to set. But afterward, you get to enjoy painting and finishing up an authentic-looking underwater rock feature.

10. PVC Aquarium Decorations by Ordinary Fish Keeper

Materials: PVC pipe, aquarium-safe paint, hot glue
Tools: Angle grinder, paintbrushes, glue gun
Difficulty: Beginner

Making these realistic PVC aquarium decorations takes a cleverly simple shortcut that makes the whole experience more fulfilling. You only need an angle grinder to carve organic grooves and chipped chunks from the piping, an almost perfect mimic for hollowed-out forest logs.

After applying several layers of brown paint for a more vivid textured look, your fish will be ready to enjoy their new hideaway. Before you add them to your tank, use hot glue to connect the pieces and give your stacked faux log aquarium decoration a lasting arrangement.

11. DIY Aquarium Decoration by Franks Place

Materials: PVC pipe fittings, silicone, lava rocks
Tools: Caulk gun
Difficulty: Beginner

Crafty doesn’t always mean complicated. A DIY rock tunnel decoration only demands a few angled PVC fittings and fire pit lava rocks, all glued together with water-safe silicone.

Combine the fittings in any shape you want before gluing rocks over the outward-facing surfaces. After a rinse to remove dust and prevent cloudy water, your lava rock decor is ready to entertain your fish. Alongside the PVC tunnels hidden behind the rock facade, natural gaps in the structure will give your fish more ways to play.



Enjoy making one of these DIY aquarium decorations. There is a DIY plan for almost everyone on this list, whether you want an easy project or something a bit more involved. If your fish could speak a human language, they will thank you for the creative addition to their home!

See also:

Featured Image Credit: naomi tamar, Unsplash

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