Hole In The head Disease (HITH)
The main symptom of this disease is the small pits, mainly on the head, which give the disease its name.
These are usually whitish in colour, and there may be yellowish mucus trailing from them. The fish may also
stop feeding and become hollow bellied.
The disease affects mainly cichlids, particularly oscars and discus, but can also affect gouramies.
The disease is linked with a protozoan parasite, Hexamita (sometimes known as Octomitus). This
may often be present at low levels in fish, but the acute infection does not occur unless factors like poor water
quality or poor diet have an influence. Therefore, Hexamita alone may not be the primary cause, and good
water quality and a varied diet should prevent this disease occuring.
The fish can be treated by isolating to a separate tank and adding either Dimetridazole (5 mg/litre) or
Metronidazole (7 mg/litre). In some countries (including the UK), these are only likely to be available via
veterinary prescription. The treatment will probably need to be repeated a few days apart, with a 20-30%
water change between each treatment. Medicated food is useful for treatment, but this can be problematic if
the fish is not feeding. Direct injection near the affected area is likely to prove very effective, but should
only be attempted by an appropriately qualified person. In the UK, Waterlife Octozin may also be used for
It also appears that a cure is sometimes possible simply by an improvement in water quality and diet in some cases.