Discus Diseases

Hopefully, this page will alleviate stress from lots of Discus, as well as their keepers. I've had a few instances of stress and disease with my fish and found it difficult to diagnose and cure them, but have managed to do it successfully (except for the "sponge" incident) - if you haven't yet, please see 3m O-Cel-O Kitchen Sponges Kill Fish!.

My hope is to make problem diagnosis and successful cures easier for you than it's been for me. I haven't seen too many pages with much extensive information on diseases, but will add them here as I find them.

I highly recommend the use of a UV Sterilizer unit on your Discus tank(s). Since I started using it, I've had no instances of any kind with parasites or disease. On a couple occasions, I've had to "dip" new fish for gill flukes, since UV doesn't affect parasites already on the fish, only in the water. But never any other problems! I just add new fish to my tanks without worry of disease transmission. Check out Water Changes for more info on UV Sterilizers!

The link on Aquaworld magazine by Dionigi Maladorno, who is a disease expert, is also a good place to start. Symptomatic Treatment of Common Discus Diseases #1 There is much good information on the page and certainly worth reading before any attempt at disease treatment. Frank Bailey also has a good article on Discus Diseases It is an excerpt from his book "Breeding Discus Successfully"


Each time I had problems with them, I'd read the books, ask the pet store people, jump out here on the Web and look for answers from the many Discus pages, as well as the general aquarium and fish medication companies' pages. It was most times confusing and exasperating. However, once you've seen things happen to them and managed a cure, it's not quite so mind boggling. Be aware also that many times, correct disease diagnosis and treatment is many times difficult, even for the experts.

If you don't use UV Sterilization, you should have a "hospital / quarantine" tank available to use for diseased fish. Just keep a few cory cats, otocynchlus, neons or other Discus compatible fish in it, in order to keep the biological filtration system going. Usually, all that's necessary in this type of tank is a sponge filter. It needs to only be a ten or twenty gallon tank. If you're going to be a serious Discus keeper, you will want to have one!


First Steps when you suspect illness or problems....

1. At the first sign of problems, the usual recommended action is to raise the temperature, gradually to 90-92 degrees and leave their light off. If they just aren't eating right, this is also a good first step, since the higher temp increases metabolism and can many times get them to eat again. High temperature can also help to naturally eradicate slight cases of internal parasites without requiring medication. If your fish is adult and seems to have come off his regular eating habits, don't be too alarmed. Adult Discus sometimes may suddenly stop eating for a few days at a time. This is not extremely common, but does happen. If you suspect it's a bacterial infection, don't raise the temperature. (See External Parasite problems below) Be careful when adjusting temperatures, as many heaters go quickly the other way! (This will depend on your heater and size of the tank) Observe the fish for a day or so and look for further symptoms or improvement. If only one or two fish are affected in a tank of many, you may wish to move them to your hospital tank, in order to prevent possible infection of others. Medication is also more inexpensive and easier to administer in a smaller tank.

2. Try and determine what may have caused your problem.... New fish added without quarantine? ..or maybe PH Shock? PH shock is a very common problem. Even though you think you changed the water and did things right, this is a common final diagnosis for unknown stress on Discus. It's very easy to get in a hurry and push your PH adjustment quickly with water changes, especially if you don't use pre-treated, stored water. It may seem dumb, but it is easy to make simple mistakes like adding some chlorinated water to the tanks, too. Be careful with this, as well.

3. Old/dirty/contaminated filter elements? If you use carbon, you may have left it in too long and it suddenly released some of the contaminants it had adsorbed. Check the whole filtration system and test the water. If you see extremely high ammonia level, your carbon has probably dumped!! If you're sure you haven't messed up with a water change, do more water changing, paying close attention to temperature and PH.

4. Quick temperature change.... They don't do well with fast temperature changes. Maybe you messed up with a water change and gave them colder or warmer water?? Or maybe you changed the temperature too fast with the heater. Any quick change more than a degree or two can stress them!

5. High ammonia level? Maybe your filtration system is not doing the job, or you're feeding them too much, causing the ammonia level to rise. Have you tested the ammonia level? Perhaps too many Discus in the tank? Recommended levels are 3-4 gallons for each small one and 8-10 gallons for large ones.

6. Determine, to the best of your ability, which type of medication to try first. See the list below of diseases and recommended treatments. If you use carbon in your filtration system, remove it all. Carbon removes medications from the water! Try the medication regiment for 2-3 days. If they show no improvement, re-install your carbon (or add it) for 24 hours to remove the meds. Medications usually cannot be mixed! Do a partial water change and then try the next one you think may work (remove carbon again before use).

7. Remember, most medications deplete the available dissolved oxygen in the water, so you need to provide extra aeration while using most medications. (Add airstone(s)

Here is a list of the most common ailments and measures that can be taken to cure them....

Bacterial/External Problems

If the fish has fin rot or some type of obvious skin problem, don't raise the temperature, but add salt at a rate of 1-2 tablespoons per 10 gallons. This can be aquarium salt, kosher salt or, as a last resort common table salt. Many external problems can be readily cured this way. Do not regularly add salt to Discus water, as is the recommendation by many for community tanks. It does, however, work well as a cure. It will dissipate with your water changes. Many medications are available for external parasite problems. Too many to list here along with the problems they cure. If your fish have extreme external problems and appear very dark, see the "Costia" section. This may be their problem.

Hexamita

This is a fairly common ailment with small Discus. It is an intestinal parasite, commonly brought on by even the slightest stress. If the fish look dark, have white, stringy looking white feces and are generally listless, this may be the problem. Most times they will hide in the back corner, usually facing the back of the tank. They may also have scalloped shaped portions of their fins missing. It can be fatal, but, if you have access to the medication necessary, it is most times curable. The problem is the medication can, in some cases, be hard to come buy. Unless your pet store can get it, you may need a prescription from a vet. It is a chemical used to cure worms in dogs and even humans. The human one is called Flagyl, the fish one is Metronidazole. The good part is, it's becoming more available at pet stores. Aquatrol, Inc. markets the product as "Metrozol". Aquatronics' product is called "Hexamit". Usual treatment is one capsule (250 mg) dissolved per 10 gallons of water. Do this every other day for 3 treatments. No carbon in the filters and be sure to have extra aeration in the tank, as most medications tend to lessen the oxygen in the water.

If the fish are still eating, sprinkle some of the powder on some on their food, then give it to them. Do this during the early stages of treatment, since whatever they expel can then be killed by the Metronidazole in the water so they aren't reinfected.

Many discus keepers recommend this type of treatment as a regular routine for all new fish in their quarantine tank.

If the fish are no longer eating and you are fairly sure it's an intestinal parasite problem, you will need to take another step with force feeding/medication. This may sound pretty weird for joe-average fishkeeper, but we disus keepers must sometimes, as you probably know by now, do some out of the ordinary things for our fish! You should only proceed with this type of treatment if you are fairly sure the fish will starve to death without doing it! It is invasive and stressful for the fish (as well as the keeper). In most cases, it works, but in some, the fish may get worse and eventually die anyway, so keep in mind it is meant only as a last effort to save the fish.

Read all of this before you begin and be sure you have a plan of action before you start! You will need a syringe of some type (obviously without a needle). Many drug stores sell syringes made for force feeding baby medication. They have a 1/8" end, which is acceptable for about 2" Discus or above. If your sick fish is smaller than 2", you'll need a smaller delivery hose attached to the syringe. Using a small plastic medicine cup, mix up a solution of about 3-5 ml of tank water, about 20 mg of Metronidazole (per fish to be treated - or about 10% of one of the tablets' contents). Then add a small amount of a good Discus food, like Tetra Bits, clean blood worms or Whattley's formula (something with some vitamins in it) and leave it set to dissolve and absorb the Metronidazole. If necessary, mash it up a bit to make sure it will pass through the syringe. You'll need to have this mixture at an acceptable temperature for the fish, so you'll want to float the container in some tank water or other warm water. While your mixture is warming, catch the fish(es) to be treated and put them in a container of tank water, so you can get them quickly for treatment. You'll also need some type of tray or dish with 1 or 2 inch sides, in case the fish decides to flop around a little while you're treating it. A large counter top is OK too, just so he can't flop himself onto the floor! You'll also need a washcloth or other clean, soft cloth soaked with tank water (just before you start). Suck up your mixture from the cup into the syringe, about 2 ml per fish to be treated. Larger fish can have more like 3-4 ml of the mixture. Lay out the freshly wet cloth (still warm tank water) and put the fish on it. Fold over part of it to cover most of the fish, except gills and head. Using a toothpick, open the mouth and insert the syringe about 1/4 to 3/8", depending on the fish's size. This can be the fun part, but take your time and don't worry too much about hurting their mouth. After all, you're trying to make them well! Slowly inject the mixture, letting the fish swallow every few seconds. Some may come out the gills, but if it all does, you don't have it in far enough. When all is delivered, leave the fish lay for another 20-30 seconds, then return to the tank. Some of your mixture will likely be dispelled through spitting and out the gills, but most should be retained in the stomach. You'll really love this part!! This type of treatment is recommended to be done at least twice. I have seen it work after just one treatment (eating normally, etc.) but the normal recommendation is every other day for 2 to 5 treatments, as necessary. Since you've chosen this treatment for intestinal parasites, you should have raised the tank temperature to at least 88-90 degrees. The fish that I had recover after only one treatment had the temp accidentally raised to 94 for a few hours. I'm not sure, but I think this may have had something to do with his quick recovery. However, I wouldn't recommend boiling them to cure diseases! I have read that increased metabolism by high temps can help them start eating again, in itself. If this force feeding treatment doesn't show improvement in the fish, you may wish to consider using a product by Aquatronics called Disco-Worm as the medication in your mixture. It is designed to treat other worms infestations such as Capillaria, Tapeworms, Copepods and Gill worms.

(Thanks to Nick Edmunds and Toni-Ann Mistretta, Discus officianados on the Discus-L mailing list for much input with this section on force feeding)

Gill Flukes...Fish may clamp one gill shut and breath heavily from the other. May also scrape themselves against tank objects in effort to dislodge the irritation. If it's the minority of the fish in the tank, you will want to give them a "bath" in a formaldehyde type product. Put some tank water in a bucket, add a product like Kordon's Formalin 3 (or something with formaldehyde) aerate the water in the bucket for sure, and watch them for any stress during the usually recommended 45 min. to 1 hr. treatment. Formaldehyde removes oxygen faster than most med's, so be careful with it and remove them at any sign of stress. If you think you have an external parasite problem, this is usually a good first choice. The entire tank can be treated, if all the fish are suspect, but be aware that the water may become clouded from killing the many parasites always present! I've seen messages on Discus-L about good luck treating gill flukes with a product by Aquarium Products called "Life Bearer". The package says that it will eliminate symptoms like shaking and rubbing of fish due to flukes and fish lice within 48 hrs. It is intended for use on the entire tank. Contains 0.0-dimethyl, 1-hydroxy, 2-trichloromethyl phosphonate.

When treating for flukes (in the tank) you should follow the prescribed treatment cycle, then do it again a few days or a week later, since these medications do not kill any eggs that may have been present in the tank during the first treatment. The second cycle will kill any that may have hatched after the initial treatment. If you fail to do this, your fish could become reinfected in a short time after just one treatment.

Costia... This is a secondary, or debility disease which occurs many times when your fish have suffered what may be a yet undiagnosed stress. They become dark and covered with a whitish-grey substance. They may look like their slime coat is beginning to dry up, especially along the lateral line (the line that runs laterally along the body near the top of their sides that sometimes looks like a "scratch" on their skin.) This problem is easily cured, believe it or not, with medication containing malachite green and formaldehyde. One such med available is made by Tetra and called "Contra-Spot". I had some fish in this condition that looked so bad, I was sure they would die, but after treating, they were back to normal within 2 days!

Stomach Bloat or Constipation...Some types of foods or overeating can cause stomach bloat, but it's not common and doesn't last long. If the fish seems very bloated for a lengthy period, you may suspect constipation. This condition can be treated by adding Epsom salts to the water at a rate of 1 teaspoon per 5 gallons of water. If this doesn't work, there are medications available specifically for stomach bloat conditions.

Discus Plague...Instead of re-writing everything here about this, now fairly rare affliction, please see the article by K. Reeves, DVM. Discus Plague

More to come here soon....as soon as I can get it up here from my notes from Internet sites, books, Discus-L email scanning and my experiences!

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