Why Is My Zebra Loach So Fat! Overweight Loach Causes

Last Updated on August 4, 2022 by cmoarz

Fish can get fat for many reasons, especially in an aquarium tank setup. You may have noticed your zebra or yoyo loach has a bigger belly than usual or a distended stomach. This can be normal, but in some cases, your loach may have a serious problem.

Since there are many reasons your loach may be displaying a large or descended belly, it’s important to take a closer look at all the factors in your aquarium tank that could be causing this issue. Once you have a better understanding of what’s going on, you can start making changes to help your loach slim down and return to good health.

yo-yo loach or zebra loach appear to be overweight, What are the reasons?

There are several reasons a loach can become fat, or appear fat. Some of these are relatively harmless and others are cause for alarm. Here are the most common reasons a loach may be looking a little chubby:

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Overfeeding is the number one cause of loches being a bit on the heavy side. It’s easy to do, especially if you have a lot of loaches in your aquarium tank. They are very active fish and will eat just about anything you put in front of them. If you’re not careful, they can easily overeat and become overweight.

Depending on what you’re feeding them, too much food can also lead to other health problems like swimbladder issues or constipation. This is why it’s so important to only feed them what they can eat in a couple of minutes and remove any uneaten food from the tank.

A loaches diet should consist of high-quality sinking pellets or granules, along with live or frozen foods like brine shrimp, bloodworms, and daphnia. They also love eating vegetables like zucchini, cucumber, and algae wafers.

If you’re not sure how much to feed your loaches, a good rule of thumb is to only put in enough food for them to eat in 2-3 minutes. This will help ensure they’re getting the nutrition they need without overeating and becoming fat.

This should be done twice a day, Usually in the morning hours, and in the evening hours.

A fat loach can also be caused by eating too much rich food, like pellets that are high in protein. While protein is an important part of their diet, too much can lead to obesity. Stick to feeding them a mix of sinking pellets, live/frozen foods, and vegetables to ensure they’re getting a well-balanced diet.

It’s important to remember that overfeeding a fish can be far more dangerous than underfeeding as it can lead to fatal health problems such as swim bladder disease or constipation.

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The older the loach gets, the slower its metabolism becomes. This means they’ll start to put on weight even if they’re not eating any more than they used to. If your loach is getting up there in age, it’s not uncommon for them to be a bit overweight.

There’s not much you can do about this other than make sure they’re eating a well-balanced diet and not overeating. As long as they’re otherwise healthy, a little extra weight shouldn’t cause any problems.

Consider cutting back a bit on the amount they eat if it starts to become too much of an issue.

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Shes carrying eggs

If your loach is female and of breeding age, she may be carrying eggs. This can cause her belly to appear swollen or distended. While this is perfectly normal, it’s important to make sure she’s getting enough to eat.

Pregnant females need a high-quality diet that’s rich in protein and other nutrients. They may also need more food than usual, so it’s important to keep an eye on their weight and make sure they’re not getting too skinny.

If you’re unsure if your loach is pregnant or just overweight, the best thing to do is consult with a specialist or your local fish store. They’ll be able to help you determine if she’s carrying eggs and make sure she’s getting the proper care she needs.

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A Cyst

Sometimes loaches can develop cysts, which can cause them to appear fat. Cysts are usually benign and don’t cause any health problems, but they can be unsightly. If your loach has a cyst, there’s not much you can do about it other than wait for it to go away on its own.

These usually happen when a loach tries to squeeze through a small space and gets stuck. The sides of the fish bulge outwards as it thrashes about, causing the cyst to form, usually from some abrasion or cut.

Most cysts will eventually go away on their own, or a loach will attempt to pop them on their own. but some may need to be removed by a veterinarian if they cause problems with the fish’s mobility or if they start to interfere

If a cyst opens up into an open wound, You will need to medicate with something like melafix, and be sure to keep the water crystal clean to avoid infections.

Most of the time these should heal up just fine as long as they are kept clean and avoid any secondary infections.

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Not all fat is actually fat, sometimes a loach can look fat because they are bloated. Bloating is usually caused by constipation or swallowing too much air. It can also be a sign of a more serious health problem like kidney disease, so it’s important to get your loach to a vet if you think they might be bloated.

Bloating caused by blockage

A blockage is the most common cause of bloating in loaches. Many times it’s caused by dry pellets that haven’t had enough time to soak up water and swell. The loach swallows them and they get stuck in their digestive tract.

If it’s a problem for your loach, the best way to prevent this is to soak the pellets in water for 5-10 minutes before feeding them to your loach. This will give them time to expand and be less likely to cause a blockage.

The best way to treat constipation is to feed your loach shelled peas. The fiber in the peas will help to move things along and get them back to normal.

Remove any other food sources while you’re treating constipation so the peas can do their job. Once your loach is back to normal, you can start feeding them their regular diet.

Bloating caused by organ failure

Organ failure is a more serious cause of bloating and can be fatal if not treated quickly. If you think your loach might have organ failure, it’s important to get them to a vet as soon as possible.

There’s not much you can do at home to treat organ failure, so the sooner you can get your loach to a vet, the better.

There are many things that can cause organ failure, such as age. So it’s important to get a diagnosis from a professional to find out what’s wrong and how to treat it.

Most times, organ failure is fatal, but with proper treatment, some loaches have been known to make a full recovery.

Bloating caused by constipation

Just like blockage, constipation is usually caused by dry pellets that the loach has swallowed and can’t digest. The best way to prevent constipation is to soak the pellets in water for 5-10 minutes before feeding them to your loach. This will give them time to expand and be less likely to cause a blockage.

The same method for treating blockage will also work for constipation. Feed your loach shelled peas to help them move things along and get back to normal. Remove any other food sources while you’re treating constipation so the peas can do their job. Once your loach is back to normal, you can start feeding them their regular diet.

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Lack of proper exercise (lack of swimming space)

Loaches need a lot of space to swim and explore. They are very active fish and will often swim long distances in a short amount of time. If they don’t have enough space, they may become more and more inactive which can cause weight gain and health problems.

The minimum tank size for a loach is 30 gallons, but the bigger the better. If you have multiple loaches, you will need an even larger tank to give them enough space to swim and explore.

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Tumors have been known to happen in loaches, but they are rare. If you notice a lump on your loach, it’s important to take them to a vet to have it checked out.

It can be hard for a none professional to tell the difference between a cyst and a tumor, so it’s always best to get a professional opinion.

Tumors can be benign or malignant and can grow quickly. If it’s caught early, surgery may be an option to remove the tumor, Although most people won’t want to spend this kind of money on a fish and euthanization is a popular option.

Luckily cancer is pretty rare in fish so don’t worry too much about it, but it’s still important to be aware of the signs and to get any lumps checked out.

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Swim bladder disease

Swim bladder disease is a condition that affects the swim bladder. The swim bladder is a sac of air that helps fish to float and maintain their buoyancy.

Swimbladder issues are usually a symptom of another problem that has caused the immune system to fail.

Sometimes, although not all the time, swim bladder issues can cause bloating which make the fish appear fatter than it really is.


Owner of AquariumGravel.com and also owner of actual Aquarium Gravel believe it or not! ;). Setting up beautiful aquarium sceneries and habitats since I was very young. Enjoy!