Making a filter safe for Betta fish

For one of the most commonly kept pet fish in America, there is shockingly little consideration given to the Betta. There is not much equipment really made for them and as a result they are one of the most improperly kept fish. This is for a couple of reasons.

Firstly, the aquarium hobby likes to focus on larger more expensive fish because they know that “real” aquarium keepers want those fish more than your everyday Walmart Betta, and are the ones looking to buy expensive equipment for their expensive fish.

Secondly, following that, Betta are a cheaper, more inexpensive fish to buy if you’re grabbing them from a local pet store, so sadly many people get them for that very reason. As the equipment making industry expects, people aren’t going to pay way more money for equipment and set up than they do for the fish itself. Either they don’t have it, because if they did they would’ve gotten a more expensive fish, or they don’t want a pet they have to spend money on, so they buy the cheapest one they can find, which will either be a Betta or a goldfish.

This leads to thirdly that Betta are marketed and sold as cheap fish that don’t need “regular fish” care. They are portrayed as some super fish that lives in mud and happens to have a short natural lifespan. The more Bettas die early with people thinking it’s all good and normal, the more Bettas the stores can sell back to them in the future. Companies know there is a market for people who want pets that are cheap, make no noise, have little smell and don’t make a mess, and they know that those people are not interested in aquarium keeping seriously. (If they knew it could also be messy and was just as much work as any other pet it would lose its appeal, since the payoff, if you don’t enjoy the hobby in itself, is very minimal for most)

But there are ways Betta keepers can have what they need for their fish to live their full, long, happy lives like any other fish. It just takes a bit more customization.

I feel comfortable saying that Bettas do much better with a filter. I don’t necessarily think a filter is necessary all the time in every set up and I think for shorter periods Bettas will be fine without one. (see previous posts) However, I will say all of my long-term success with Bettas always involved a filter. Simply put, because of their anatomy they can live without one, but I just don’t think they can thrive indefinitely that way unless you have a much better set up, care system and time devotion than I did, and I had a fair amount.

On the flip side of that, filters can be extremely dangerous to Bettas if the keeper is not vigilant and diligent with what they choose and how they set it up.

It breaks down like this, Bettas have been bred to have beautiful, flowy fins above all else (except the plakat tail type that more closely resembles the wild Betta tail shape). Therefore, they are not always strong swimmers, relying mostly on their little pectorals (the ones they flutter on their sides). Other fish don’t have these problems, so the guards or cages on filters are made to keep the body of a fish from being sucked up through the intake tube of the filter, they are not made fine enough to keep delicate, long fins that other fish species don’t have from being sucked inside. Luckily this is an easy fix.

I have modified the intake on two different types of filters recently. One had no guard on the intake tube, so I bought a fish scooping net made to catch the fish and cut the net part off. With just a square-ish piece of water safe netting, I stretched it over the bottom of the tube and secured it with a rubber band. This creates a fine enough guard that even fins won’t get sucked inside and ripped apart, yet water can still get through.

Note: if you are using rubber bands make sure they’re not dyed or perfumed in any way etc. Also replace them when they start to break down in the water.

Another note, you’ll have to take the net off and clean it fairly frequently, maybe even weekly depending on your set up because it is so fine and will grow algae and clog up quickly if not kept clean. If it does that, the motor can struggle to pull in water and burn up, ultimately breaking your filter.

A second way to modify an intake is to leave the original guard on the tube. I found, in my local pet store, a filter sponge. It was a cube of blue sponge, hollowed inside and filled with carbon pellets. It was made to be inserted in a filter to help chemically filter impurities from the water. (more on filters to come). All I did was remove the top of the sponge that was precut and empty out the carbon. I then slid the intake tube into the hollow middle of the sponge and secured the sides tight around the tube with a rubber band. The depth of the sponge happened to be enough to cover the length of the guard at the end of the intake tube. Because the sponge was made to be in a filter, it was made to have a lot of water pass easily through it, so it really didn’t block the water from going into the filter at all. Not all types of sponges may be as good for this, but any type of filter sponge should be able to do the job. My Betta now sits atop the sponge in his free time.

The other filter part that needs to be altered is the output, where the cleaned water from the filer flows back out into the aquarium. Going back to how Bettas aren’t good swimmers, they don’t necessarily come from bodies of water that have a great amount of current. It can stress them out and lead to illness if it is overwhelming and they cannot get away from it. Lots of fish species love current, so lots of filters are made to create current in their output. There is one easy way I have personally used to lower a current from an output myself. The water on my filter dropped off a little lip and fell to the aquarium like a waterfall. First I raised the water level so the fall was as little as possible, then I took an empty water bottle and cut off the top above the lable and the bottom below the label. I then removed the label and cut up one side so that I was left with a “C” shaped piece of plastic. I then secured the plastic over the lip so that it curled under the waterfall. The water was running out of the filter and falling on the plastic then running out each side of the submerged plastic in a dispersed lesser current. I can post some pictures of the process if it’s helpful, but I have since seen several places online that have almost identical step by step instructions with pictures.

With those steps done, you protect your fish from getting sucked into the filter, and protect them from getting pushed around constantly by what comes out of the filter. It makes it so that any filter really can work for a betta. They do truly make water quality so much better, which is really the key to a fish being happy and healthy. Since using filters, I have seen my fish brighten in color, regrow some ripped and missing fins and become more active and overall healthy. They really make all the difference when done properly and are really a piece of equipment to invest in (though not all are that expensive and there are some great deals out there!). If you want what is really best for your fish I think you’ll be glad you did. I can talk more later about why some people don’t think that filters are necessary for Betta, but all I can say from my experience is they may not need them all the time to live, but they definitely need them to thrive. I’ve said it before, water quality is the most important part of their life.

I am not a handy person and I’m sure there are many other ways out there to make filters safe for Bettas. But I think anyone can make these ideas work and I really think they should. Like any other living animal, Bettas deserve proper care. It only takes a little while to set up a safe filter and it will make all the difference for the rest of their lives. With less force on output, filters are also typically less noisy, and having a finer guard to clean, keeps more particles from having to be cleaned out of the inside of the filter! It’s a win-win for you and your fishy friend.

For an extra note: when in doubt you can always buy a filter rated for more gallons than what’s in your aquarium. It will do a better job cleaning. Remember that monitoring the flow and having current going in and out of a filter is more of a problem the smaller the tank, when you get into the very small, because the fish can literally not escape it and rest.

Of course other equipment, like a heater is also necessary for a great aquarium, but we’ll get to that later. Water quality should be a top priority, and this is a pretty easy way to help it. I hope something in here is a little helpful. The bettas I have kept with filters really came into their full colors and finnage and are absolutely beautiful; and I wish I would’ve known to use them sooner!

Don’t forget, diy filter changes CAN go horribly wrong, if you’re like me and make mistakes before finding the right way that works for you BUT that’s a story for another time. Give a filter a chance and make it safe for your fish to change their whole world for the better.


Until next time, love from me and Luxe (my betta)



Author: BettaSplendids

Just a person with a passion for what I would humbly consider the most wonderful and underrated fish in the aquarium keeping hobby; seeking to share information, stories and ideas!

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )


Connecting to %s