5 Popular Large Aquarium Decoration Ideas You Can Try!

Have you ever seen a home or an office with an aquarium installed? It’s hard not to be drawn toward one.

From fish, crabs, snails, or any other kind of water, life is fun and relaxing to watch. You might even talk yourself into having one and wonder about large aquarium decorations ideas for the future.

That big aquarium tank can seem relatively empty depending on how many sea creatures you have swimming and crawling around. So how can you fill the space?

If you’re looking to add elements to your large aquarium besides marine life, it can be fun to include non-swimming decorations in your tank as well. Recently, large rock-style decorations are becoming more popular for large aquariums.

Even some small aquariums can benefit from one of these large decorations (depending on the size of your aquarium), but be careful. It’s still a good idea to leave your fishies some space to swim!

Here are a few cool things to put in a fish tank for you to try in your new large aquarium! Try one or try them all!


Top 5 Large Aquarium Decorations to Choose From

One crucial safety tip before you add a rock-style decoration into your aquarium is the presence of sharp edges on the rocks. If you have a Dremel tool, a file, sandpaper, or similar tool, you may want to smooth out any sharp points or edges that could harm your fish.

Also, keep in mind the types of fish that you have. Most fish (especially smaller ones) like to have a place to hide from other fish, so a decoration with a lot of little (and big) nooks and crannies can help keep your fish safe and secure.

Mountain Pillars

FEDOUR Aquarium Mountain View Stone Ornament Tree Rock Cave Landscape, Large Aquarium Ornament Rock Artificial Fish Tank Decoration

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Give your aquarium an unforgettable landscape for your water-dwelling critters to enjoy. These towering mountain pillars soar to 11-inches at the peak and stretch 10.2-inches in length, creating a realistic backdrop for your fish tank.

This decoration is made of a safe, non-toxic resin that will not affect your sea creatures. It also comes with six small artificial aquarium plants that you can place around your mountain.

Some fish may like to swim around the mountain and explore its craggy shape, while others may be content just cruising around the smaller plants on the aquarium floor. So what do your fish like to do?

Now all you’ll need is an octopus named Ringo for your garden under the sea!

Mountain View

UR MAX BEAUTY Large Fish Tank Decorations, Mountain View Aquarium Ornament Tree House Cave Bridge Fish Tank Decoration

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Here’s another undersea mountain-style aquarium decoration. It’s easy to imagine an underwater mountain range in your aquarium with this decoration. At nearly 14 inches wide, this one is wider than tall, which should fit better in wider aquariums. The height is just over nine inches high.

It is also made of a safe, non-toxic resin, and it should fit just fine in aquariums up to 55 gallons in size. It also comes with three miniature plants to satisfy your underwater green thumb.

There are many nooks and crannies within the rocks for your marine life to explore and have adventures in. Can your fish find them all? Whatever happens, don’t let them get lost!

Another great idea could be using these mountains around some Castle Aquarium Decor.

Ancient Rock Face

Sunyiny Aquarium Decorations Fish Tank Decorations Ancient Rock Face House Exotic Aquarium Ornament Aquarium Decor for 20 30 Gallon Fish Tank

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This decoration is the most mysterious of all! It’s a tall tower-style decoration (over 10 inches high), so make sure your aquarium is large enough.

It is made of a safe, non-toxic resin and is suitable for freshwater and saltwater aquariums. It has an incredible amount of detail that is bound to look amazing in your large aquarium. Also, if you have underwater lights, this decoration would look amazing in your aquarium lit up at night in a dark room!

This one has six different openings for your sea creatures to swim around, hide, and explore. (Can fish play hide and seek?)

Ancient Tunnel Ruins

Pet Products Fish Tank Decorations Ancient Tunnel Ruins Ornaments Ornament for Aquarium Monster Large

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Some decorations are best suited for smaller tanks, and this one is a good example. At less than six inches tall, this one can fit in virtually any size aquarium.

It’s a Buddha Head style decoration with a large gaping mouth that serves as a tunnel so that small or large fish can enjoy it. It’s also suitable for fresh or saltwater aquariums and is made of a safe, non-toxic resin. It may be small, but it packs just as much mystery and fun as a large aquarium decoration does!

Speaking of mystery, how did a Buddha end up underwater anyway?

Large Tree Stump Cave

AQUA KT Aquarium Landscaping Tree Stump Hole Rock Cave Cichlid Stone for Fish Tank Decoration

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Sometime in the past, on a distant shore, a large tree stump was flooded and ended up underwater. Fish and other sea life flocked to the remains of the mighty tree and made it their playground. Now your fish can enjoy the same fun in your aquarium. Instead of ancient wood, this tree is made of a safe, non-toxic resin and is compatible with salt or freshwater aquariums.

This decoration is a bit smaller than the others, only about five inches in height. So it would be possible to fit several even in a moderate-sized aquarium. You can imagine an underwater forest in your aquarium if you add many!

But be careful, though, since this is a smaller decoration, the openings are also smaller. So if you have large fish, this decoration might not be the best for your aquarium.



Now we’ve seen some great large aquarium decoration ideas for your large aquarium! Which one do you like best? There are many other types of large aquarium decorations to choose from, such as sunken pirate ships, secret divers, coral reefs, and many more, so go out and make your fishies happy!

There are a lot of great choices for a large aquarium here, but for my fish and me, I like the Ancient Tunnel Ruins decoration. The Buddha’s face is so intriguing. And I want to know how this Buddha ended up underwater!

Maybe someday he’ll tell my fish…

Jack Dempsey
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