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How to Run Multiple Fish Tanks on One Filter (In 4 Steps)

How to Run Multiple Fish Tanks on One Filter (In 4 Steps)

The purpose of this blog is to share general information and is written to the author's best knowledge. It is not intended to be used in place of veterinary advice. For health concerns, please seek proper veterinary care.

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So, you have a lot of fish tanks but not enough filtering power. What’s there to do?

There’s no need to despair over getting another filter.

Running multiple fish tanks on one filter is a smart decision for numerous reasons. One of them is cutting down on costs.

On the other hand, the process itself may prove somewhat tricky. You may encounter a few hiccups on the way.

We’re here to provide you with a detailed step-by-step guide on how to run multiple fish tanks on one filter.

Why Run Multiple Fish Tanks on One Filter?

Your first reason might be to reduce your costs by spending less on more filters. However, while that is true, there are other reasons you could run multiple fish tanks on one filter.

Finding the right tank size can be difficult if you’re looking to host several fish of various breeds.

If you want to expand your aquarium radius without buying a larger tank, combining multiple tanks is the answer. By having a two-in-one tank, you might as well use one filter.

Another reason you could consider running multiple fish tanks on one filter is if you’re trying to breed your fish.

You’ll want extra space, meaning you could resort to fusing tanks together and using one filter.

If you look from a practical point of view, you will notice that multiple fish filters are a hassle to keep up with. One filter would be easier to take care of.

4 Steps to Run Multiple Fish Tanks on One Filter

We recommend going through the steps a few times before starting. They might be tough to go through.

If you’re unsure about running multiple fish tanks on one filter, you can always resort to some good ol’ professional help from an aquarium shop.

Now, on to the steps.

Step 1: Preparing Your Equipment

Before you get your hands on any fish tanks, you’ll need to prepare your equipment.

Since you’re combining fish tanks, there are a couple of options you can go with. The easier option would be to get a PVC piping unit with some elbows, and a saw to cut through them.

We recommend getting clear pipes if you want to see your fish floating around.

Otherwise, you can optionally use glass to build your bridge. With the glass, you’re going to need glass cutters and sandpaper to file it down.

To stick the glass together, we advise getting silicone along with a caulking gun for better control and grip.

Another tool you could get is a tube with a valve and polystyrene attachment. It’ll act as a vacuum to clear any air from the bridge so that the water remains inside.

A right-angle ruler will give you the best guide to follow when building your angled bridge.

Step 2: Building Your Bridge

Now that you’ve got your tools ready, it’s time to build your bridge. We’ll discuss how you can create your fish tank bridge using a PVC pipe.

You’ll want to start by measuring out the pipes, getting the right size compared to your tanks.

If you want to make any adjustments, simply cut them with a saw and make sure to file them down with sandpaper. This will prevent any particles from going inside your aquarium.

Afterward, you’ll need to create your makeshift bridge by connecting the pipes with elbows. In this instance, you’ll want to connect an elbow to each end (approximately four).

Following the fitting, now’s the time to stick everything together. Grab your caulking gun and silicone to seal the pipes and elbows together to prevent any potential leakage.

Your pipe bridge should be ready by then. Next, you should make cuts on the hoods of your tanks for the pipes to enter through.

Step 3: Creating the Water Flow in the Bridge

This is a bit of a technical step. You can’t simply put your pipes in and call it a day; the physics won’t allow it.

You’ll want to vacuum out the water using the tube with the valve and polystyrene attachment.

After placing the pipes inside the tanks with the clear pipe above the tank, insert the tube inside one of the pipes until it reaches the bridge area.

Suck out all the oxygen from the inside (yes, using your mouth). Make sure to use the valve to keep the oxygen you sucked outside.

At this point, you should notice the water level rising in the PVC clear pipe.

Step 4: Adding Your Filtration System

Filtering two tanks isn’t a simple task. You’ll need a powerful filtration system adequate for two, or more, tanks.

We advise looking for sump filters. Contrary to some beliefs, sumps aren’t actually filters, but they host a filtration mechanism inside their tanks.

These sorts of devices filter large volumes of water, or in this case, two or more fish tanks attached.

It would be best if you avoided canister filters since they aren’t as accommodating to large tanks as a sump filtration system.

What to Consider Before Running Multiple Fish Tanks on One Filter

Before hopping onto this project, you need to consider a few things that could potentially damage your tanks.

Since you’re joining two or more tanks together, the likelihood of a disease, bacteria, or pathogens spreading around is much higher.

You also need to be more careful with the inflow and outflow of water from one tank to the other. That being so, you run the risk of flooding one of the tanks.

After knowing a couple of risks, we advise you to think twice before running multiple fish tanks on one filter.

Final Thoughts

Following our discussion on how to run multiple fish tanks on one filter, you might feel slightly overwhelmed, especially if you’re doing it from home.

Nonetheless, if you own several tanks at a shop, these steps will prove helpful.

The hardest step in this guide is building your bridge. Once you’ve got that down, the rest is a breeze.

You’ll only need to add your filtration system, and you’re in business. Good luck!