Here is other info I found on treatment...
Other Treatment
The antibiotic metronidazole (chemically labeled [2-methyl-5-nitro- 1-imidazoleethanol] and synonymous with "Flagyl," the trade name for this benzimidazole derivative and antitrichomonad for the treatment of human reproductive and urinary tract flagellated protozoan infections (frequently of the genus Trichomonas, i.e. T vaginalis, among others) is very effective at a rate of 20 milligrams per gallon of water, added weekly for a period of three weeks. Monitor water quality for measurable levels of dissolved nitrite (NO2-) during treatment. Remove carbon from filters, if used. Fifty-percent of tank water should be changed before each treatment.
Be certain to replace the amount of metronidazole removed when performing more frequent water changes. In severe infestations, 250mg metronidazole per 10 gallons of water every other day for four days, with at least 50% water changes prior to each treatment, may be more effective. Still more effective is daily dosing of 250mg metronidazole per 10 gallons of water for five days, with water changes before each treatment. Metronidazole may be removed from the water column via carbon and/or water changes.
Another treatment method is as follows: perform a 50% water change followed by a dose of 500mg metronidazole per 10 gallons of water. Change no water until the third day, when a 50% water change is performed followed by a dose of 250mg per 10 gallons of water. Repeat this 250mg dosage and water change regimen on the fifth, seventh, and ninth days. It is a ten day treatment. The reasoning behind this method is to hit the protozoan hard with the first dosage, and to finish it off with the remainder of the treatment.
When treating discus in conjunction with metronidazole, elevate water temperature to approximately 92ºF. This will increase the effectiveness of metronidazole, a "design drug" that works best at a temperature of 98.6ºF as it was originally intended for use with humans (do not elevate water temperature to this degree). It may also help to bolster the fishes' immune system and should weaken Hexamita, leaving it more susceptible to treatment. This should not be done If other species of fish intolerant of this high temperature are kept with discus.
If fishes are still consuming food it is advisable to pre-dose food with metronidazole as well. 100mg per tablespoon of food is an ideal starting point. Flake food may be moistened, measured, and mixed with the medicine, then frozen and fed in small servings; this method may be applied to other frozen foods, i.e. beefheart based preparations. Feed medicated food for at least seven days. During this time, feed no other foods. Take care to ensure that food is consumed immediately following introduction into tank water, so that as much of the medicament is consumed as possible. Allow frozen foods to thaw before feeding.