Malawi Bloat

What is Malawi bloat in fish

Malawi bloat,despite looking like fish dropsy, is a different aquarium fish disease commonly characterized by abdominal swelling ^[1]. It is also known as cichlid bloat since originally it mainly affected African cichlids native to the three lakes – Malawi, Victoria, and Tanganyika ^{[2, 3]}. Malawi bloat is essentially not a disease but a symptom of an underlying condition, often turning fatal for aquarium cichlids ^[4].

What are the causes of Malawi bloat

Since the reasons for the occurrence of bloating in fishes living in African rift valley lakes have remained largely unknown, many possible causes have been speculated:

• Addition of large quantities of common salt into the fish tank with the purpose of increasing the pH of soft water in the aquarium to create a more natural living environment for your fish (although the water in African rift lakes has a pH value 8.0-8.9 and hardness between 200 and 400 ppm, you will not achieve the desired alkalinity by adding common salt) ^[3].
• Poor water conditions resulting from irregular water changes, improper denitrification (due to insufficient aeration), and overfeeding. These factors may weaken the immune system of the fish, thereby causing it to be stressed, making it susceptible to parasitic or bacterial infections of the intestinal tract ^[3].
• Inappropriate diet, causing improper digestion and excretion may irritate their intestinal walls. Herbivorous Malawi fish have long gastrointestinal tracts and commonly suffer from such intestinal issues ^[3].
• Clostridium difficile, an anaerobic bacterium, produces protein toxins that bring about fluid accumulation and localized death of tissues or cells. In a study, the bacterium has been found in the bloated intestine of the affected fish and is possibly responsible for causing Malawi bloat in cichlids ^[5].

What are the symptoms

As in dropsy, Malawi bloat may make the affected fish look like a pinecone with its scales sticking out, with other symptoms including reduced appetite, and an increased breathing rate ^[4]. The following symptoms may also be exhibited:

• Sluggish behavior
• White, stringy feces
• Red marks around the anus
• Ulcers on different parts of the body ^[4]

How to prevent it in your fish

Feeding regularly in appropriate quantities as well as maintaining proper water quality and a healthy environmental condition is a significant factor when it comes to preventing abdominal bloating in aquarium fishes ^[6].

• You may feed algae-based, veggie mixed Spirulina flakes and pellets to herbivorous cichlids ^[3].
• Give small amounts of brine shrimp but avoid high-protein fish foods containing animal fat and meat because cichlids are primarily herbivores ^[3].
• Always give fresh food to your fish ^[3].
• Add some calcium and magnesium mix to make sure the aquarium water is well-filtered, oxygenated, hard, and alkaline ^[3].
• Replace 10-12% of the tank water every week ^[7].

How to treat Malawi bloat in flowerhorn, betta, goldfish, gourami, and other fishes

Since this type of bloating is difficult to treat, early detection of the disease along with an optimization of water condition is important for improving the likelihood of recovery ^[6].

Treating Malawi bloat at home

• Separate the affected fish by moving it to another tank. For improving the water condition, perform a partial water change by replacing 30% of the quarantine tank water ^[2].
• Remove filter cartridges or inserts containing zeolite or activated carbon since they could absorb chemicals, including medications used for treatment ^[2].
• Add one teaspoon Epsom salt per 10 gallons of aquarium water, as it will help in raising the pH and simulate the natural living environment of African cichlids ^[2].

You can transfer the fish back to the main aquarium after the symptoms have subsided and the sick fish shows signs of recovery.

Medicines for Malawi bloat

Talk to a vet immediately if the condition does not improve after trying the above home remedies.

The vet may prescribe antibiotics like metronidazole, melafix, or octozin since they are useful for controlling bacterial and parasitic diseases in fish ^{[3, 8]}.

Treating with Clout

You may alternatively use one tablet of Clout, an antiparasitic medication, in about 10 gallons of aquarium water. Administer the medication once every 24 hours for two consecutive days initially, treating it at full strength on the first day and a half strength on the second day. Then, change 80% of the water and do the treatment at full strength on the 4th day ^[3].

Do not feed the affected fish until its treatment is over, and be sure not to stop the medication suddenly without talking to the vet. If you see any signs of stress possibly caused by the medication, immediately perform a 75% water change ^[3].

Consult your vet before using any of the medications on your fish.

Can Malawi bloat be cured

A complete cure is only possible if the sick fish is treated immediately after the detection of the disease in its mild stages ^[6]. Without prompt treatment measures, the disease might cause severe damage to the liver and kidney, which could prove fatal ^{[1, 6]}.

Is Malawi bloat contagious

There is much debate regarding whether the disease can be easily spread to others. However, the affected fish should always be quarantined to minimize the risks of water contamination, preventing the healthy fishes from getting stressed.