is supported by our readers. When you buy through links on our site, we may earn a commission. Learn more.

The Ins and Outs of Betta Fish Poop

Believe it or not, fish poop is a topic of increasing interest among aquarists. Like any aspect to your pets, the more you study it the deeper the rabbit hole becomes.

Betta Fish Poop

So what is there to learn about Betta fish poop? Let’s dive in together!

Do Betta Fish Poop?

Like any animal that eats not every part of their meal is nutritious. Anything not used by the body needs to be expelled. All of this waste is what makes up Betta fish poop!

So how do fish poop? As it turns out it’s very similar to any other animal, including us humans. When fish eat something it gets moved to the stomach where the digestion process begins. Some fish actually don’t have a stomach: food simply heads straight to the intestines.

Betta fish do have a true stomach, however. Here, food is partially broken down and made easier to digest. Acids also help kill any unwanted bacteria that hitchhiked inside or on their meal.

Once food reaches the intestines most of the nutrients within it are absorbed into the bloodstream of your Betta. Once this process is complete waste heads to the anus where it is released as fish poop. 

Fish don’t have as complex an inner system as we do. Not all fish have a large intestine and none have a colon where water is absorbed and feces are stored. Fish poop simply reaches the end of the line and is expelled! After all, if there is one thing fish have an abundance of, it’s water! So no liquid reabsorption is required.

Poop Hanging From a Betta Fish

Poop Hanging From a Betta Fish

Walking to the tank to appreciate the beauty of it, you might find yourself sometimes surprised by a long string of poop hanging from the bottom of your Betta fish. Is poop hanging from a Betta fish a problem!

Believe it or not that is entirely normal. Betta fish poop contains not only fish waste but also mucus, bacteria, and the exoskeletons of their prey. All of this can sometimes act as a binding agent, which holds the waste together as it’s being expelled. In short, you get long strings of poop hanging from your Betta. 

This can happen with any kind of fish poop. Sometimes it just refuses to break away from the anus. If you end up seeing a long string of fish poop, don’t worry!

The Color of Fish Poop

That said, the color of Betta fish poop can tell you a lot about the health of your fish. Fish poop should be brown, red, or tan in color. Unless your fish are vegetarians, in which case green is also okay!

If the hanging fish poop is clear, white, or pale yellow, it’s often a sign that something is amiss inside. Liquid-like pale fish poop can also indicate diarrhea, just like in people. It may be that there is a bacterial infection taking hold or a meal simply doesn’t agree with your Betta fish.

What About a Constipated Fish?

Poop Hanging From a Betta Fish

Constipation is where fish poop is unable to fully move inside of your Betta fish. It’s not common but it does happen. When this occurs the Betta will look bloated and likely not be swimming very much due to the pain and stress. It will hang around the surface or bottom, listless, and likely won’t try eating. And of course, you won’t see it pooping regularly like it usually does.

If you have a constipated Betta fish you need to act quickly because constipation can be fatal in just a few days if left untreated. However there is a lot of misinformation out there on the Internet that you should be wary of. One of the most common but useless bits of info out there is that you should feed peas to a Betta fish that is constipated.

How to Cure Constipation in Betta Fish

How to Cure Constipation in Betta Fish

I’m here to tell you that you should absolutely not feed your Betta fish peas, under any circumstances! At best they will do nothing – but they are also likely to make things worse.

The idea is that the fiber contained in peas will help move things along inside. That’s great – if you are a human or another animal that can work with it. Betta fish are carnivores and tiny ones, at that. Fiber can simply make blockages worse by absorbing water or feeding block-causing bacteria even more. In fact, it’s often the fiber and carbohydrates in poor quality Betta food that cause constipation to begin with! So no peas for your Betta fish.

Instead, find an aquarium store that has live or frozen daphnia (water fleas) for sale. Daphnia are aquatic crustaceans that are a natural source of food for many carnivorous fish, including Bettas. 

And best of all, they have chitinous exoskeletons that provide gentle roughage, helping to move along anything that is stuck inside. In short, they are an excellent Betta fish laxative (so don’t feed daphnia very often)!

Another question to ask is whether the water is too cold. Bettas, like all fish, are ectothermic. This means that their metabolism is regulated by their environment. The warmer they get the faster their metabolism proceeds and vice versa.

Keeping a Betta fish, which is a tropical fish, in cold, room temperature water is a great way for constipation to arise. The digestive system slows enough that food starts to rot within before it is expelled. Bacteria and gas cause blockages which can quickly become fatal. So always provide a Betta fish with a heater. They can survive in cold water but prefer warm conditions like those found in their native Thailand (75-84℉).

Does Your Betta Have Parasites?

Does Your Betta Have Parasites

You may have heard that fish are prone to getting parasites and this is true. External parasites like ich and flukes – but also internal ones. Worms are by far the most common internal parasites and they typically live in the intestines where they find a ready supply of food and blood from their hosts.

Betta poop is one way you can diagnose whether your fish has parasites or not. Occasionally a few worms may get trapped inside and expelled along with the fish poop. So it’s a good idea to occasionally examine it to see if any parasites are there.

Parasites can also be occasionally seen squirming from the anus if the infection is very heavy. A heavy parasitic infection will also manifest in other ways, including drastic weight loss, ragged fin, and an insatiable appetite. But sometimes you will actually see the worms sticking out of the fish.

Make sure that what you are looking at is actually a worm. The reproductive organ of most fish is a pale, round or pointed thing that may look like the end of a worm. It is usually readily visible after a heavy meal or in the case of females, when her eggs are developing, adding pressure to her insides.

Fortunately, internal parasites like worms are very easy to treat. They respond well to medications like Prazipro!


Fish poop is not a very common topic! But as you’ve read here, there is a lot to learn about the subject. Normally you simply want to remove it each time during a water change with little fuss. But by studying your Betta fish’s poop you can tell a lot about its health!

Jason Roberts
About Jason Roberts
Jason is an aquarium fanatic that has been a fish hobbyist for almost three decades.

Leave a Comment