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Why You Have A Bloated Molly And How To Fix It!

Mollies are starting to becoming increasingly popular within the fish keeping hobby as more and more people start to keep them in their tanks.

Although molly fish are generally considered to be very beginner friendly fish, they can commonly have issues and we have noticed a number of people reaching out to ask about caring for a bloated molly in their tank.

The most common reason that a molly will bloat up is due to the fish having dropsy that can be a serious issue for most mollies.

Less common and less serious reasons that a molly may bloat up include swim bladder disease and an infection of internal parasites such as worms in the fish.

Although both swim bladder disease and an internal parasite infection are also serious, they do tend to be less common in mollies than dropsy and so we will focus on this disease in this article.

Thankfully, both internal parasites and swim bladder disease are also easy to treat in your molly fish.

Is It Normal For A Molly To Bloat Up?

It is not normal for a molly to bloat up and a bloated molly is always a sign of a potentially serious issue with the fish. If you notice that your molly is bloated, it is important to take action quickly as the fish may die if the issue is not treated.

The majority of the less common causes of bloat in a molly are usually very easy to treat while the condition is also slow to develop.

Unfortunately though, dropsy is much harder to treat and often leads to the death of the fish even with treatment. This is why it is so important to be proactive and take action as soon as you notice that your molly is bloated.

Our regular readers will know that we are huge fans of taking action as soon as you noticed a problem with any of your fish.

This is because the sooner you take action, the more likely it is that you will be able to save the fish.

In addition, it is also important to remember that mollies are very sensitive to changes in water quality and so even a slight change can cause them to become temporarily bloated with this often looking like dropsy in some cases.

What Causes A Molly To Bloat?

The most common reason that your molly will be bloated is due to the fish having dropsy. Sell common and less serious reasons that your molly will bloat up include swim bladder disease, internal parasites, and pregnancy.

In very rare situations, sudden water changes in a tank with mollies can sometimes cause them to bloat up temporarily.

Dropsy is a serious and often fatal condition that affects molly fish. The most common symptoms of dropsy in a molly fish include the fish being bloated, scales standing out from the body, and loss of appetite.

In extreme cases, the fish may also have red lesions on their skin due to the potentially extreme swelling.

Swim bladder disease is a common and less serious condition that can cause your molly fish to bloat up. The most common symptoms of swim bladder disease in a molly fish include the fish floating at the surface of the tank, swimming in an abnormal way, and loss of appetite.

Internal parasites are a common problem in molly fish and can cause them to bloat up. The most common symptoms of internal parasites in a molly fish include the fish being bloated or swelling, a loss of appetite, and parasites often being in the poop of the fish.

The poop of your molly can often be white or red in color and may also contain blood when suffering from an internal parasitic infection.

Pregnancy is the final most common reason that your molly fish will be bloated. The most common symptoms of pregnancy in a molly fish include the fish being bloated with the bloat being strictly contained to the belly of the molly rather than all over its body like the other causes above. The gravid spot of the molly will also darken in color when the fish is pregnant.

As we mentioned above, sudden water changes can sometimes cause your molly fish to bloat up. This is usually due to the stress that the fish experiences from the change in water quality and is often temporary.

Other symptoms of toxic shock from water changes include lethargy, Clamped fins, and a loss of appetite.

How Do I Treat A Molly That Is Bloated?

It is actually very difficult to treat dropsy in mollies and the fatality rate is still high even if you start treatment within a day of noticing the issue.

Many people within the fish keeping community will keep a suitable dropsy treatment on hand so that they can instantly start to treat for dropsy as soon as they notice it but even then, the fatality rate is still high.

Swim bladder disease in a molly can be treat in a number of ways with there being some medical treatments on the market.

Some people will also feed their molly peas and although this treatment can work, people can’t seem to agree on why it actually works with some saying its due to peas having an active ingredient to treat the swim bladder disease in the fish.

Other people say it is due to peas sinking causing the fish to try and dive in its tank to eat the pea resulting in excess gas being released from the fish.

When it comes to treating internal parasites in your mollies, we would always recommend that you use a commercially available chemical treatment.

The most common treatments for internal parasites in fish are praziquantel and metronidazole. These treatments will usually come in the form of a pill that you will need to dissolve in the tank but there are some liquid variants of the treatments available.

There are a number of DIY or natural treatments for internal parasites such as dosing the food of your mollies with garlic. Although this does work, it is not as effective as the chemical treatments while also being more difficult to reliably use with your mollies too.

There are a number of water conditioning products on the market that you are able to use to treat your molly fish for the sudden change in water quality.

These products will help to remove any harmful chemicals from the water that could be causing your fish stress while also helping to make the water more comfortable for your fish too.

You should always consult with a veterinarian before starting any treatment on your molly fish as they will be able to give you specific advice on how to treat your fish depending on the exact cause of the bloatedness.

Is Dropsy In A Molly Contagious?

Dropsy is not a contagious disease in your fish so there is usually no need to quarantine an effected fish unless the other fish in the tank are bullying it.

In some cases, the underlying cause of the dropsy may be contagious though but it will be likely that all of the fish in a tank will already have it.

This is why people who try to treat their fish for dropsy will often just treat their full tank rather than quarantine one fish and treat it. This usually makes it much easier to treat all of your fish at once to try and save them.

Unfortunately, if you have to order your dropsy treatment online and wait a couple of days for it to arrive then it may already be too late for the treatment to work on your fish. Dropsy can develop quickly and often prove fatal within a few days in some fish.

How Do I Know If My Molly Is Pregnant Or Bloated?

The easiest way to tell if your molly is bloated or pregnant is by looking at its gravid spot. This is a black patch on the underside of the fish that becomes more visible when the fish is carrying eggs.

A pregnant molly will only be swollen on the belly area where as a bloated molly will usually be bloated all over the body.

If you are unsure whether your molly is bloated or pregnant then we would recommend taking a trip to your local fish store or contacting a veterinarian for help.

An experienced fish keeper in your local area may also be able to help you but you will commonly find that sharing photographs online on fish keeping forums will often be able to help you get confirmation too.