One of the toughest choices in the goldfish hobby?

Choosing your aquarium background.

If you’re like me, you want your tank to look classy – not like a photo you’d see in one of those old-school 90’s books on fishkeeping.

But good news:

It’s possible to transform your goldfish tank background with a touch so professional and lifelike everyone will compliment it.

And it will make a HUGE difference in your aquascape.

So what’s my all-time favorite?

3D rocky background by Universal Rocks.

It’s made out of non-toxic fish safe silicone and natural crushed rock

… And looks absolutely SMASHING.

Realistic, neutral tone and simple to install.

Plus, it won’t ever dissolve and will last a lifetime!

With foam-based 3D rocky backgrounds, I get concerned about toxins leaching into the water or the product dissolving over time.

(Also I’ve also found it pretty much impossible to find one that doesn’t look like it was painted on.)


You can’t go wrong with this, it looks just amazing and will bring your tank to life.

Another plus is that the background is not bulky at all so it doesn’t take up much extra room in your goldfish tank.

Here are the sizes it comes in:

  • 10 Gallon (20 x 12″)
  • 15 Gallon (24 x 12″)
  • 20 Gallon High (24 x 16″)
  • 20 Long (30 x 12″)
  • 29 Gallon (30 x 18″)
  • 30 Gallon (36 x 12″)
  • 40 Gallon (36 x 16″)
  • 55 or 75 Gallon (48 x 20″)
  • 90 Gallon (48 x 24″)
  • 125 Gallon (72 x 20″)
Check Prices on eBay

Get this:

I discovered that the 55/75 gallon size is also available on Amazon for the lowest price….

…even lower than on the manufacturer’s website!

Depending on the size of your tank this might even be the most cost-effective solution if you can cut it smaller to size.

Check Price on Amazon

As you can see, there’s an option for nearly every aquarium size.

And if your tank is not a standard size, the good news is this background can be cut to fit as you need.

Please note that the measurements above are for your external tank size. The backgrounds themselves are approximately 1/2″ shorter for each dimension in order to properly fit inside the tank and allow for the width of the aquarium walls.

How does it look so real?

The original mold was taken off of a beautiful Basalt rock formation.

Pretty neat, huh?


They also make a ledge version for a 48 x 20″ aquarium that’s also quite beautiful.

Check Price on Amazon

Secret Tip…

Many goldfish keepers like to have a bare-bottom fish tank.

But the glass bottom doesn’t have a very natural look.


Not only can this be a fish tank background for goldfish…

This material can also be used at the bottom of your tank if you like a bare-bottom aquarium.

Be sure to silicone it down fully as it does want to float, unless you use rocks large enough that your goldies can’t move them.

Siliconing it to the bottom will also prevent waste and debris from getting trapped underneath it.

How to Install a 3D Rock Background for Your Aquarium

Before installing, it’s recommended to wash it to reduce water cloudiness issues.

A pressure washer or strong garden hose pressure will do the trick.

Because it’s a flexible material, some people even use it for corner tanks by bending it to fit.

To install it, you can either use clips to hold it in place or adhere it to the back wall of the (empty) tank with aquarium-safe silicone.

(Apparently most people who use clips do so for reptile enclosures since they may not be as effective at holding it down underwater.)

This is important:

Your tank will need to be totally emptied and dried to silicone.

Alternatively, some people find it sufficient to hold in place with filters at the top and their gravel substrate at the bottom, no need to clip or silicone.

For others, it seems the gravel just doesn’t cut the mustard to keep the thing weighed down sufficiently.

The tank background can be cut with a box knife or kitchen boning knife if needed to accommodate your equipment.


If you use silicone, it needs to cure for 48 hours before you add water and fish.

Putting the tank on its back should really help through the siliconing process.

Oh, also:

Be sure to use silicone that will not harm your fish.

You can get aquarium-specific silicone for peace of mind OR purchase 100% silicone at your hardware store (look for GE Silicone 1 Windows & Doors, it should be 100% silicone with no mold-inhibitors which are toxic to your fish).

Final Thoughts

There are a lot of different approaches for a goldfish tank background.

But I think you’ll agree with me that this is one is a sure-fire way to bring your tank to the next level and create a natural looking environment for your water puppies.

Those old-school stick on the back backgrounds sure do pale in comparison to the realism of faux stone.

I love that this background is made out of natural stone too and is non-toxic to the fish.

(What could be worse than putting something potentially poisonous in your tank and killing your finned friends!)

So what do you think?

Have you ever tried using a 3D rock aquarium background for your tank?

I would love to hear your comments below!