The key is avoid rich meaty foods as proteins in excessive amounts can cause bloat. If your cichlids pseudotropheus, then focus on vegetable matter more than meaty foods. Here's a summary.
Dropsy of Aquarium Fish
Synonyms:
Bloat, Malawi Bloat
Symptoms:
Protrusion of scales, distended abdomen, pop-eye
Causes:
Dropsy has several possible causes: poor water quality, poor food quality, bacterial infections, intestinal flagellates, excessive proteins (especially to purely vegetarians)
Longer periods of stress can weaken the fish's immune system thus enabling the bacteria to enter the fish's body. At this stage, it becomes increasingly difficult to remedy the situation. The disease begins with a bacterial infection of the intestines resulting in the excretion of slimy fish wastes. In the course of the disease, parts of the mucous membrane of the intestines come off. They stay at the anus of the fish. Even if the fish keeps taking up the food, it cannot digest the food anymore leading to the malfunctioning of the internal organs. The amount of water the fish takes in then cannot be expelled and the excess liquid gather in the body cavity resulting in the protrusion of scales and eyes.
Excessive proteins can also cause bloat among fish, mbunas most especially as the fish cannot effectively digest the proteins in their stomachs. Herbivorous fish have longer digestive systems that are not designed to digest excessive proteins in comparison to the carnivores' shorter digestive system. Do not feed your herbivorous fish foods that contain too much protein.
Treatment:
Epsom salts, metronidazole, kanamycin sulfate
Treatment may not be effective as the disease itself is internal making it difficult to treat and determine the exact cause.
