Learn to Build a Fish Bridge Between Aquariums

Have you ever wished your tropical fish had more space to swim around, but you don't have the money for a bigger aquarium right now? No problem. If you have a spare aquarium or can afford a second smaller aquarium, you can create a water bridge that increases the area available to your fish by connecting two or more aquariums.

And additional benefit to this method is that it can make aquariums easier to clean, since you can move the fish to one of the other aquariums and close off the bridge for cleaning.

Here's what to know about making your own DIY water bridge for fish aquariums.

What's a water bridge?

HOW TO: aquarium water bridge by The king of DIY

A water bridge is just a tunnel that connects two aquariums from above. It comes out the top of one aquarium and goes down into the other, so that the ends are submerged in water in separate tanks. When done properly, water flows through the tunnel so that fish can swim through.

Why build a water bridge?

In addition to creating more space and providing options for easier tank cleaning, a water bridge provides enrichment for your fish. Not only does the tunnel itself create an interesting space for fish to explore, but it also means your fish can go from one tank to another to experience different environments.

If you want, you can make the separate aquariums as different from each other as you like.

One thing to keep in mind, however, before starting this DIY project is to make sure the fish in each aquarium can get along with each other. If you wouldn't keep them in a community tank together, then they shouldn't have their aquariums connected by an aqua bridge—it's as simple as that. Just as with any community tank, you should make sure there's enough overall space for the individual fish to be happy and healthy.

What materials do you need to make a bridge for fish?

You can make water bridges out of several different materials. Glass is a popular option because it's safe for tropical fish and is usually what the aquariums themselves are made of, creating a matching aesthetic. After all, part of the joy of fishkeeping is creating a beautiful or interesting aquarium, and you don't want the tunnel to ruin the aesthetic.

To create a glass aqua bridge, you only need a handheld glass cutter to cut the glass into the shape and size of the tunnel you want. Then you connect the separate pieces with watertight silicone.

You can get tips on creating a glass water bridge by watching this video:

That being said, if this is your first time creating a DIY water bridge, you may want to go the simple route and use PVC pipes and elbows. You'll have less cutting, measuring, and assembly that way. Using clear pipes allows you to see the fish moving through the tunnel, as well as allowing you to monitor the water to make sure air bubbles are getting in and breaking the vacuum.

Here’s a good video that demonstrates the PVC pipe bridge:

To get water flowing through the tunnel from one tank to another, you'll need to use a flexible tube to siphon air out of the tunnel, allowing the water to flow through. Removing the air creates a vacuum that keeps the water inside. That's some pretty cool science.

When it's all done, it's a really cool look. Let us know on The Tye-Dyed Iguana Facebook page if you've built a water bridge for your tropical fish.