If bloat suddenly occurs in one your discus fish it is most likely not an internal parasite. A leading cause of death among healthy discus, goldfish and other tropical fish is from overeating. This usually occurs in the larger, prettier and most aggressive eater. If this problem occurs in a one and a half inch or smaller discus that has failed to grow properly, the cause is usually a defective digestive tract as a result of improper feeding as a fry and the result is usually fatal. The condition I am addressing will be seen usually in a lone single discus. Proper diet and feeding techniques reduce the occurrence of overeating in healthy discus, three inches and larger.
Discus need small, frequent feedings, not large ones. Their stomach is not designed to hold large meals. Overeating can easily result in constipation. As the food sits in the gut it begins to decompose and rot inside the fish. Bacteria, gas and fluids are created, resulting in swelling and pressure on the swim bladder, which in a discus sits on top of the stomach. This results in loss of balance which affects the ability to swim properly. The discus will either sit on the bottom or hang in the water facing down or up as it cannot properly keep it's balance. As this progresses, the swelling in the gut increases and the abdomen becomes very distended, looking like a balloon ready to pop. The buildup of gas and fluid causes the eye to become distended, creating a Popeye effect. A hazy, cloudy look may appear on one or both eyes as bacterial growth increases. The discus fish may create extra slime and become dark, fins may become clamped and the fish will not eat. Using treatments labeled for Popeye in tropical fish will not cure this discus.
For now forget about internal worms or parasites. A swollen belly is almost always assumed by the new discus hobbyist to be internal parasites. But even heavy tapeworm infestation does not give the extreme bloated appearance of overeating. Internal parasites are microscopic with the exception of tapeworm and a couple others not common to discus. On that note gill flukes and external parasites common to discus are also microscopic.
If you have recently added some new fish and suddenly several fish are exhibiting swollen bellies it could be bacterial. The most common bacterial infection is Aeromonas. There is no single physical or behavioral sign specific for Aeromonas infections. Infected fish frequently have: small pinpoint hemorrhages at the base of the fins or on the skin, distended abdomens, and protruding eyes. Internal signs include: fluid in the abdomen, swollen liver and spleen, and the intestines are distended and fluid-filled. This is the classic Popeye bacterial infection found in tropical fsh. and while it is a real threat, 99% of the hobbyists I counsel on this issue have a discus fish with constipation from overeating.
Treatment - The discus fish must eliminate the bowels quickly to prevent death. This is done with water changes and Epsom salt (available at any drug store and most grocery stores), a laxative that works on discus. Each case is different so there is no one set standard dose. First change a volume of water equal to the amount you are already changing on a regular basis. Then add one tablespoon Epsom salt for every ten gallons of water the aquarium holds. Thus, a 100 gallon aquarium receives 10 tablespoons. Add an identical dose of Epsom salt in four hours and one more in 4 more hours if the fish has not started elimination. Look carefully the following day to determine if the fish has evacuated. If not, repeat the exact treatment done on day one beginning with the water change. If needed, repeat again the third day.
If on day two you see the fish has evacuated, change a volume of water equal to the amount you are already changing on a regular basis and replace just the amount of Epsom salt removed by the water change. In 24 hours change water again but do not add Epsom salt. The Epsom salt will be removed by water changes over time. Begin feeding with frozen bloodworms or frozen brine shrimp in small amounts.
If the fish has eliminated but the stress of the ordeal has resulted in loss of appetite, it will be necessary to treat the fish with metro for a few days to restore the appetite. Metro blends such as metro plus are not recommended as they are mostly salt and fillers. You need the pure metro to see results. The pills are not nearly as water soluble or effective as pure metro powder which is water soluble, pure and effective. Usually a daily dose of pure metro, 1/4 teaspoon per 20 gallons for five days restores appetite. Once the fish is eating continue the metro for 3 more days. I do provide the pure metro on my food and medication page of my web site, http://www.RockyMountainDiscus.com/Food_and_medications.htm
Prevention: One thing that contributes to a discus overeating is the use of a plastic worm cone for feeding frozen or live worms. The idea is to keep the worms in one place and keep them from getting scattered. However, they really should be scattered so everyone gets a fair share. And although the discus grab food as it enters the water, they like to graze along the bottom. Using the cone teaches the discus to compete for food, training the largest most aggressive eater to dominate, and possibly overeat.
Avoid feeding discus fish freeze dried foods. They can swell up in the stomach, even after soaking in a liquid, and can cause this condition. Also the nutrients are lost during processing. Be very careful with foods made of fish meal, as discus do not easily digest this. Frozen foods rarely cause this problem if presented properly. Frozen bloodworms can be placed in a small Tupperware container of tank water for 60 seconds before pouring into the tank. Although frozen foods thaw instantly when hitting the water, this prevents any discus from swallowing a large chunk of bloodworms.
Labels: discus fish bloat, popeye, swollen belly