Common Name:  Ich (or Ick)

Pathogen/Cause: Ichthyophthirius multifiliis (FW) , Cryptocaryon i      -rritans (Marine counterpart)

Physical Signs: Distinct, sometimes slightly-raised white spots that look very similiar to grains of salt or white sand on the skin.

Behavioral Signs: Scratching against objects (skin irritation), clamped fins, may "hang" and gasp near surface if infection reaches the gills.

Potential Treatment: Numerous treatments: brand names include Mardel's Maracide or Coppersafe, Jungle's Ick Guard, Aquarium Pharmaceuticals' Super Ich Cure, treatments that contain formalin, etc. Take special note of warning labels; copper is not safe for invertebrate animals or plants, malachite green (ingredient in large majority) is dangerous for scaleless fish and many small tetras (halve dosage). Marine formulations slightly different. Most medications not tolerated well by corals and inverts. Best treatment for marine fish is QT, feeding garlic and use of cleaner fish/shrimp.

Other Notes: Perhaps the most common disease of pet fish. Tends to attack stressed fish, especially with rapid temperature and pH fluctuations. Easily treatable with caution if caught in time, but may be recurrent if not treated for at least a week. Cysts live in gravel, has multiple life cycle stages, read my article for more treatment options. Water changes, raising temperature (to speed life cycle), darkening of tank, etc. all recommended. Guard for secondary infection of wounds by bacteria.Certain fish, such as gymnotoids (FW), hatchetfish (FW), batfish (SW) and tangs (SW) especially susceptible.

Common Name:  Hole-in-the-Head Disease (HITH)

Pathogen/Cause: Spironucles sp. and Hexamita sp.; debatable and controversial whether they are the true pathogens that cause it.

Physical Signs: Holes that widen the sensory pores in the heads of large fish (this in itself is more aptly ascribed to HLLE, head and lateral line erosion, which in turn is related to a variety of water quality factors, not necessarily an infectious parasite). May exude pus.

Behavioral Signs: Often asymptomatic until serious; general signs of lethargy, may have trouble swimming due to loss of balance.
Potential Treatment: Medications that contain mentronidazole;

Brand names: Jungle Hole-N-Head, Aquatronics Hex-A-Mit, Aquarium Pharmaceuticals General Cure, etc.; however, there is controversy over whether or not the parasite is the major causitive factor, medication may not be necessary; see information linked at right.

Other Notes: Watch for secondary bacterial infections. Often attacks large fish fed with live foods. Cichlids are especially susceptible. Please check World Cichlid's page on HITH/HLLE which has much more detailed info, theories, and potential treatments of this disease. Also, Dr. Barb's Flippers and Fins Site has some more info for curious minds.

Common Name:  Neon Tetra Disease (NTD)

Pathogen/Cause: Plistophora hypessobryconis

Physical Signs: Loss of color in the red stripe and/or milky/brownish coloration, pale area beneath the dorsal fin.

Behavioral Signs: Sluggishness, erratic swimming, separating from the school, weight loss, occasionally in advanced stages ends in a secondary bacterial infection that causes bloating and pop-eye.

Potential Treatment: No known dependable and consistent cure, though many claims are made.

Other Notes: NOT species specific to the neon tetra. May also infect other small tetras and fish such as danios. Highly contagious, usually considered incurable (some claims made, no proven studies confirm them), and inevitably fatal. Quarantine suspect animals immediately.