12 DIY Plans to Build Your Own Aquarium Decorations (With Pictures)

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 Top 12 DIY Plans for Building Your Own Aquarium Decorations

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.

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.

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.

There are multiple ideas for shapes and designs you can make with Sculpey polymer clay. You can also paint these creations to suit your tank, as long as you use aquarium-safe glue. Building décor from scratch will allow you to have the most unique decorations on the block.

How complex this project is will be dependent on your comfort level using polymer clay and how complex you choose for the designs to be. If creating a large item, you may need to make it in pieces and attach the completed pieces together with aquarium-safe glue or silicone.

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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From diagnosing illnesses and providing correct treatments to proper nutrition, tank maintenance and water quality advice, this book will help you to ensure your goldfish are happy and to be the best goldfish keeper you can be.

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.

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.

This DIY refuge cave idea is a great way to use up those CD cases that are collecting dust on your childhood bedroom shelf. This is a relatively easy project, but you’ll need to use extreme caution cutting holes out of the cases, as well as sanding down the edges to prevent injuries to your fish.

This project can be a great way to use up extra supplies you already have at home, including things you are no longer using. It comes together quickly and can be ready to go into your tank in a day or two. Just be extra cautious with those sharp plastic edges.

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.

Got an old terracotta pot lying around in the garage? Give it a good wash and get to work on this decorated terracotta pot aquarium decoration. You’ll only need a pot, some gravel, and an aquarium-safe adhesive. This is a beginner-friendly project and can even be done by kids.

You can select gravel or rocks that match your tank’s substrate if you’d like. However, there are some bright-colored and glittery types of aquarium gravel on the market today, which could really create a striking appearance in your tank. This decoration doubles as a hiding place for some of your more shy pets.

If you’re overwhelmed by the idea of working with cement, then this DIY aquarium bowl might be the perfect starting point for you. You’ll just need something that is bowl-shaped. This DIY uses a hollowed-out watermelon, but you can use disposable bowls as well.

In this DIY, they are using the created bowls as a fishbowl, which is likely to be far too small for any fish. However, this can be a fantastic DIY to add into your tank. You can use it as a planter, to hold rocks or other décor, and you can even create an entrance and flip it over to use as a cave.

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.

Conclusion

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!

Featured Image Credit: naomi tamar, Unsplash