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Symptoms: Obvious white spots on the body and/or fins of the infested fish. Spots may resemble grains of salt. The spots (actually, cysts) may be up to 1 mm in diameter, or may join together to form irregular patches. Heavily infested fishes may scratch themselves on the bottom or tank decor, and rapid respiration may be evident.

Life Cycle: Adult parasites, which feed upon the tissue of the fish, fall into the substrate layer. There, they divide many times, producing several hundred tomites which are the infective stage. The tomites swim into the water column in search of a host and, failing to find one, die in a short time. If they do find a host, the tomites attach and encyst. The life cycle is temperature dependent, and can occur in 3 to 4 days at 70 dF and up to five weeks at 50 dF. At lower temps, the parasite will remain dormant.

Treatment: As long as the parasite is encysted on the fish, it is immune to treatment. However, at the first notice of these cysts, treatment should be started. Malachite green is generally safe to use for most freshwater species. I know some of you must be shaking your heads, saying that malachite green will kill some freshwater fish species. NONSENSE! When dosed correctly, malachite green is safe for even the most so-called sensitive species.
The correct dose is 0.05 ppm malachite green for three treatments, one every other day. At this level, your fish should not experience malachite sensitivity. We advise the use of Kordon's Rid Ich, Kordon's Malachite Green or Aquatronics Green-Ex. If dosed following the directions on the bottle, you will be well within the therapeutic range.

Another popular treatment is the use of aquarium or marine salt. Bringing the level to 3 ppt will generally eradicate the parasite. Some catfishes may be sensitive to this salt level, and so if you do have catfish in your tank, go no higher than 2 ppt. In either case, use whatever level you choose as an indefinite bath.

Also, it has been noted that raising the temperature will also "cure" the condition, but I would advise against this for several reasons:

1) An increased temperature also increases the metabolism of the fish, which causes it to require more oxygen. However, there is less oxygen in the water the higher you go with the temperature. This produces more of a stress on the fish, and may delay a full recovery.

2) The use of temperature alone is not necessarily a cure. While it may accelerate the life cycle, it does not guarantee a 100% kill.

Symptoms: Yellow-grey coating on the skin and fins, making the fish appear as if they have been covered with gold dust. Fish may scratch constantly, and rapid respiration is usually noted. In heavily infested fishes, they may be noticed hanging just below the waters surface or in the outflow of the filter. Spots, if noticed, are smaller than those of Ich.

Life Cycle: Adult parasites, called dinospores, attach themselves to the skin, fins, and gills of the fish. After 3 to 7 days in this stage, the dinospores fall off the fish and into the substrate and multiply into 200 or so infective spores. These are released into the water column and swim about until they change into mature dinospores, and reinfect the fish. Dinospores can survive for several days without a host.

Treatment: As long as the parasite is encysted on the fish, it is immune to treatment. However, at the first notice of the gold-dust condition, treatment should be started. Perhaps the easiest and most effective popular treatment is the use of aquarium or marine salt. Bringing the level to 3 ppt will generally eradicate the parasite. Some catfishes may be sensitive to this salt level, and so if you do have catfish in your tank, go no higher than 2 ppt. In either case, use whatever level you choose as an indefinite bath until all signs of the disease are gone.

Acriflavin (neutral) can also be used at a dose of 5 to 10 mg/l (ppm) as a continuous bath for 7 to 10 days. Please note that this chemotherapeutic will kill some types of aquatic plants. If you are using acriflavin hydrochloride, the dose is 10 ppm for 2 hours, but note that this chemotherapeutic is NOT as safe as acriflavin (neutral), and is not advised.

Malachite green and formalin are generally safe to use for most freshwater species. I know some of you must be shaking your heads, saying that malachite green will kill some freshwater species. NONSENSE! When dosed correctly, malachite green is safe for even the most so-called sensitive species. The correct dose is 0.05 ppm malachite green and 15 ppm formalin for three treatments, one every other day. At this level, your fish should not experience malachite sensitivity. We advise the use of Kordon's Rid Ich, Kordon's Malachite Green or Aquatronics Green-Ex. If dosed following the directions on the bottle, you will be well within the therapeutic range.

Also, it has been noted that raising the temperature will also "cure" the condition, but I would advise against this for several reasons:

1) An increased temperature also increases the metabolism of the fish, which causes it to require more oxygen. However, there is less oxygen in the water the higher you go with the temperature. This produces more of a stress on the fish, and may delay a full recovery. In the case of Oodinium, the parasite usually attacks the gills first, damaging them to the point where oxygen exchange may be severely hampered.

2) The use of temperature alone is not necessarily a cure. While it may accelerate the life cycle, it does not guarantee a 100% kill.

Signs: Argulus are a flattened disk shaped parasite with what looks like two eyes on its anterior dorsal end. They are found attached to the skin of the fish via suckers, and feed upon blood by means of the sharp mouthparts which are inserted into the fish. At the point of attachment, a raised ulcer may be noted. It is here that secondary infections (bacterial/fungal) may occur. This condition is most common on newly imported or pond raised fish, especially goldfish, although other fish may be affected.

Life Cycle: Adult Argulus attach themselves to the skin of the fish and then mature adult females leave the host and prepare to lay eggs. These eggs are laid in gelatinous capsules that stick to any surface. The eggs hatch out within three to four weeks, and the first of may juvenile stages is released. The first juvenile stage must find a host within a few days, otherwise it will perish, whereas the adult stage can survive up to ~15 days without a host. The eggs and adults of this parasite may winter over without apparent harm, only to reinfest the fish once the water warms.

Treatment: Treatment for this parasite is two-fold. first, any obvious parasites should be CAREFULLY removed from the fish. This is accomplished by using a pair of fine forceps or tweezers, grasping the parasite firmly at midbody, and pulling firmly. You should then dab any wounds with merbromine. This type of removal will need to be done every two weeks or so. You will also need to treat the system in which these fish reside. Dylox (a.k.a. masoten) at a rate of 0.75 ppm for three treatments, each five days apart, is perhaps the best and most easily available remedy. Of course, purchasing fishes from non-infected stock is your best bet. Please note that dylox is considered a carcinogen, and care should be taken when using this chemotherapeutic. Dylox is harmful if swallowed, inhaled, or absorbed through the skin. The use of latex gloves and a chemical respirator is advised. If swallowed, wash out mouth with water and call a physician. In the case of skin contact, flush affected area with water for at least 15 minutes, and remove contaminated clothing. If inhaled, remove to fresh air. If breathing becomes difficult, call a physician. Dylox is also a cholinesterase inhibitor. If a fungal infection is noted along with the Argulus, 0.05 ppm malachite green should also be added to the water for three treatments, each two days apart.

Signs: A grayish-white film will be noted on the skin of the fish, and is especially apparent on the eyes or darkly pigmented areas of the affected animal. Swollen gills and ulcerated areas may be noted in advanced cases. Such fish will generally tend to hang either at the waters surface or at the bottom of the tank. NOTE: This disease is highly contagious, and care should be taken that cross contamination does not occur.

Treatment: Generally, malachite green is your best bet for an effective treatment. I know some of you must be shaking your heads, saying that malachite green will kill some freshwater species. NONSENSE! When dosed correctly, malachite green is safe for even the most so-called sensitive species. The correct dose is 0.05 ppm malachite green for three treatments, one every other day. At this level, your fish should not experience malachite sensitivity. We advise the use of Kordon's Rid Ich, Kordon's Malachite Green or Aquatronics Green-Ex. If dosed following the directions on the bottle, you will be well within the therapeutic range. You want to dose at least three times, once every other day for three treatments. Another treatment is to bring the salinity of the system up to 2 ppt to 4ppt as an indefinite bath. If catfishes are present, I would advise the lower dose. If no catfishes are present, go with the higher dose.

Signs: A grayish-white film will be noted on the skin of the fish, and is especially apparent on the eyes or darkly pigmented areas of the affected animal. Swollen gills and ulcerated areas may be noted in advanced cases. Such fish will generally tend to hang either at the waters surface or at the bottom of the tank. NOTE: This disease is highly contagious, and care should be taken that cross contamination does not occur.

Signs: Lernaea are elongated slender parasites with what looks like two tails on it posterior end. These tail like structures are, in actuality, egg sacks. The male Lernaea is somewhat short lived, and is usually not seen. Lernaea are found embedded in the skin and muscle tissue of the fish, and the rest of the body trails away from the body of the fish, giving the appearance that the fish has streamers coming off its body. At the point of attachment, a raised ulcer may be noted. It is here that secondary infections (bacterial/fungal) may occur. This condition is most common on newly imported or pond raised fish, especially goldfish, but can affect any fish.

Life Cycle: Female Lernaea embed them selves into the skin of the fish and prepare to reproduce. Once the female has matured, eggs are then released from the tail-like sacks that form on the posterior end. These eggs soon hatch out into the first free living juvenile stage, which must find a host within five days, otherwise it will perish. Once a host is found, the first juvenile stage molts into subsequent juvenile stages, which are parasitic. From there, the cycle continues. This cycle takes ~25 days at 68 dF and may fail to complete at below ~59dF. The eggs of this parasite may winter over without apparent harm, only to reinfest the fish once the water warms.

Treatment: Treatment for this parasite is two-fold. first, the female parasites should be CAREFULLY removed from the fish. This is accomplished by using a pair of fine forceps or tweezers, grasping the parasite firmly at the point of attachment, and pulling firmly. You should then dab the wound with merbromine. This type of removal will need to be done every two weeks or so. You will also need to treat the system in which these fish reside. Dylox (a.k.a. masoten) at a rate of 0.75 ppm for three treatments, each five days apart, is perhaps the best and most easily available remedy. Of course, purchasing fishes from non-infected stock is your best bet. Please note that dylox is considered a carcinogen, and care should be taken when using this chemotherapeutic. Dylox is harmful if swallowed, inhaled, or absorbed through the skin. The use of latex gloves and a chemical respirator is advised. If swallowed, wash out mouth with water and call a physician. In the case of skin contact, flush affected area with water for at least 15 minutes, and remove contaminated clothing. If inhaled, remove to fresh air. If breathing becomes difficult, call a physician. Dylox is also a cholinesterase inhibitor. If a fungal infection is noted along with the Lernaea, 0.05 ppm malachite green should also be added to the water for three treatments, each two days apart.

Signs: Fishes so affected often have a swollen belly, and scales may stick out at 90 degree angles from the body, giving the fish the appearance of a pinecone. A red vent and ulcerations may also be present, as may long, pale fecal casts. Fluid may accumulate within the body cavity.

Occurrence: Since dropsy may be caused by one or more factors, it is difficult to point to one common cause.

Treatment: Once the first signs of dropsy are noted, the infected fish should be started on a 14 day regime of antibacterial medicated food. A 24 hour bath in 2 ppm nitrofurazone is also indicated. If you can bring the fish to a vet, you may wish to administer ceftazidime at 30 mg/kg IM for three treatments, each two days apart. Since this is a rather expensive treatment, it is usually reserved for larger and more expensive fish. If it is a bacterial problem, this should clear it up. At the same time, an examination of the fishes environment should be made. How is the water quality? Is the diet adequate for this species, and is it being fed a variety of fresh foods? Have live foods, especially Tubifex worms, been fed? If after 14 days this condition does not reverse itself, you have to consider that the problem is either viral, metabolic, or genetic, none of which are treatable. In some cases, the kidneys of the fish may simply shut down, causing an accumulation of fluids. The best thing to do here is to painlessly euthanize the fish. The best way to do this is to place it into a small container of water, and place that in your freezer. The fish will painlessly "go to sleep" as the temperature drops, and all body processes will stop