How To Create A Baffle For Your Betta Filter

What is a filter baffle?

A filter baffle is a way of modifying a filter to ensure that the output / return rate doesn’t create too much of a current / disturbance in your aquarium. A baffle tends to be a guard modification of some kind that is placed in front of the output to absorb and dampen the water ejection.

Why Baffle?

Bettas are fish that don’t naturally fight against a current in the wild; they live in calm waters. Having a strong current in your aquarium can therefore stress your betta and worse, tire your fish to an unhealthy state. A strong output can also cause the surface water to break, which can make a betta fish uncomfortable and wary, causing it to surface less frequently for oxygen. Not surfacing enough for oxygen can be bad for a betta fish’s labyrinth organ, and lead to illness.

It’s common for betta keepers to baffle their filters – it’s an easy modification and there are plenty of great tutorials online. There are many filters on the market that are great for bettas in most aspects, but have too strong an output. This applies to both filters that are built into aquariums (see some of our favourites here), and separate filtration units that you add to an existing tank. Baffling is a great way counteract this downside.

It’s worth mentioning that not EVERY filter needs a baffle. It depends on how and where the filter is positioned in the tank and, depending on the size of your aquarium, the output may not cause an unhealthy disturbance. Not every filter has a particularly high output to begin with, and some filters can be easily adjusted out of the box.

How to baffle

A homemade baffle isn’t expensive or hard to make. In fact, as demonstrated in the images below, it can just be made from a plastic bottle cut into a particular shape. You can also use a cup, a piece of plastic, or even a sponge.

When making a baffle, be sure to use a material that won’t affect the water quality. Aquatics companies don’t tend to make baffles, so it’s unlikely you’ll be able to buy an ‘official’ one for your aquarium. However, they’re super easy to make – sometimes it may take a little bit of initiative and experimentation, but that will just make your betta setup even more unique. Trying to modify it for your filter may take a bit of thought but it shouldn’t be anything time-consuming. There’s an eBay user that even sells 3D printed baffles for a few specific filters and aquariums – pretty awesome if you want an aesthetically pleasing look.

Example of a Baffle

This first example is one we created as part of our video series on setting up a betta tank, which is part of our premium membership plan.

In this case we used a sponge (like this one on Amazon) to create the baffle.

Sponge filter on a nozzle style filter

Different filter types require different baffle Types

There are usually two ways of baffling a filter, and these differ depending on the standard output / return dynamic of the filter.

There are two ways that a filtration unit will return water to the aquarium. It can either return through a nozzle, or it can trickle (somewhat like a waterfall) from a lip.

Here are two photos to demonstrate the differences:

Waterfall type filter:
Waterfall style filter
Nozzle type filter:
Nozzle style filter

The dynamic of the filter will affect how you baffle it. In the images below, you can see a few examples of baffles being used on the two different types of filters.

More photos of Baffles

Baffle on a nozzle style filter
Plastic baffle on a nozzle filter
Plastic baffle on a waterfall filter
Sponge baffle on a nozzle filter

Some of the photos in this article are taken from Spec-Tanks, which is a great website to check out if you are thinking of modifying your betta tank.

See a video of Us creating a baffle

Our Bettaboxx Premium membership includes a video course where we show you how to set up a betta tank from start to finish.

The course includes a video on filtration, and within that video we demonstrate how to baffle a filter using a sponge.