“Malawi Bloat” may be the name of this feared cichlid disease, but the truth is that it affects all cichlids from Africa, whether they are from Lake Malawi, Lake Victoria and especially from Lake Tanganyika.
Malawi Bloat is mostly a death sentence for the fish it affects. The cure success is lower than with all other diseases. The key is therefore to avoid it altogether. But for this, we need to understand all we can about this disease.
- The first symptom is a loss of appetite. This is why regular observation of your cichlid tank is so important. If you do not take immediate action at this point, other disease characteristics follow and you will most likely lose your fish. These secondary characteristics include abnormal swelling of the abdomen (hence the name “bloat”), an increased respiratory rate, a tendency to reclusiveness, white streaky feces, and either sitting on the bottom of the tank, or lingering at the surface. Red marks around your fish’s anus, or skin ulcerations might also be apparent.
- If you noticed nothing before and only now see these secondary symptoms, it will probably much too late to rescue your fish, because by this time extensive damage has already occurred to the fish’s liver, kidneys, and/or swim bladder. Death typically results within 24-72 hours after the onset of these secondary symptoms, although some fish may hang on for more than a week in this condition. It is not typical for more than one fish to be ill with this condition at a time, but other infected tank mates usually tend to die off at intervals of a week or so.
- Malawi Bloat is primarily characterized by a distended stomach. Without an immediate decrease in feeding, the disease then advances to a point where the stomach acquires a cylindrical appearance. In extreme cases, the entire fish appears swollen, and the scales will stand away from the body, giving the fish the appearance of a pine-cone. Indeed, when this affects goldfish, it is often referred to as “Pine-cone disease.” This body swelling is more properly called ‘ascites’.
- Bloat is indicated by the stomach being uniformly distended; if the swelling is more of a lump than a swelling, it is probably a tumor, which is almost always incurable. Postmortem examinations of fish which die from Bloat show the livers covered with a yellow, fatty substance. Secondary bacterial infections usually occur, but chances are that this is simply the result of the stress caused by liver failure and possibly by kidney failure as well.
The good news is that three of the main causes for “Malawi Bloat” have been identified:
FIRST: The addition of large amounts of salt (NaCl) with the intent of simulating a more natural habitat. True, the rift lakes of Africa are alkaline and have very hard water with a pH of 8.0-8.9, and a General Hardness between 200-400 ppm, but common salt will not alkalinize your tank.
What makes water “hard” is a combination of dissolved calcium and magnesium. If you have soft water and need to raise the pH/hardness of your water, I suggest you use SeaChem’s Cichlid Salt, and/or the use of crushed coral as a substrate. Rocks, like limestone, are also helpful in raising the pH of aquarium water, but because minerals don’t stay suspended in water for long, it’s important to do frequent water changes. We discourage you from using any wood in the tank, as it will only serve to lower the pH of your water, even if its effects are minimal.
SECOND: Long term exposure to poor water conditions. Poor water conditions stem from infrequent water changes, a lack of sufficient aeration (for the denitrifying bacteria), and especially from overfeeding. All three of these factors leads to elevated nitrate levels in the water. Fish are very good at fighting off disease on their own, but when exposed to poor water conditions over a long period of time, they become stressed and their immune systems no longer function at optimal level (just as with us!). What actually causes the diseased condition seems to be a parasite that is always there but only becomes invasive when the fish is stressed. There is still some disagreement as to whether it is actually a protozoan or bacterium that causes the intestinal tract infection.
However, it cannot be emphasised enough: African cichlids are very sensitive to water quality. If you do not keep up a regular weekly water change routine, and keep on ensuring that your water conditions are impeccable, you are playing with fire!
THIRD: Improper diet and Overfeeding. In fact, overfeeding is probably the primary cause of Malawi Bloat. The old adage, “feed your fish what they can eat in five minutes” does not apply to the majority of cichlid species. You should only feed what they will eat in a minute or two. If they are not eating voraciously, cease feeding your cichlids for at least two days. (It may surprise you, but it may be actually be better for your cichlids to feed only every other day!)
Herbivorous Cichlids have long intestinal tracts, and therefore, it is quite common for them to have intestinal problems. Just to give you an idea of how long they really are, Cichlids’ intestines are FOUR TIMES their body length!
The decomposition of improperly digested, or improperly excreted foods can irritate the intestinal wall, and stress the fish, giving the invasive parasite a foothold. This often comes about when a primarily herbivorous, algae scraping cichlid (like Tropheus spp.) is fed high protein foods such as bloodworms, or pellet and flake foods containing large quantities of fish meal. In light of this information, and experience, it is important to avoid certain foods, and to go light on others.
This is a thin, red worm that lives in mud of rivers, and is usually collected from polluted rivers. By feeding Tubifex to your fish, you are exposing them to the diseases these worms may be carrying.
Red blood worms
Some people have fed bloodworms lightly, without any known incidents; however, those in the know caution against them.