Common Name: Ich
Scientific Name: Ichthyophthirius multifiliis
Symptoms: white spots on body appear to look like sugar sprinkled on fish, darting, rubbing body against tank decor, sometimes no symptoms other than spots
Cause: stress, poor water quality, most common in water under 78˚F [25.5˚C]
Medications: RidIch+ by Kordon
Ingredients: formalin, malachite green
Notes: Because the Ich parasite is only visibly present 4 out of the 7 day lifecyle it is important to continue to dose for the full recommended number of days
Ich (Ichthyophthirius multifiliis) is a contagious parasitic infestation that commonly affects both marine and freshwater fish. The Ich protozoan may be present in the water without you even knowing it. It often only preys on fish that are stressed due to poor water quality or other stressors.
A fish that has the Ich parasites on him will look as though he has been sprinkled with little granules of sugar or salt. A mild case may only turn up two or three small white dots but a severe case could leave your entire fish dotted with white parasites.
A fish with Ich may become twitchy and try to rub its body up along the tank décor or gravel. In severe cases the fish may become lethargic or loose it’s appetite. It’s not uncommon, however for the fish to act pretty normal despite the parasites being present.
Ich is quite easy to treat but left too long can be fatal. It’s very important to understand the life cycle of the Ich parasite in order to treat it properly. The protozoan has a three-part life cycle of which it is only vulnerable to treatment for approximately two days out of its life. Because some fish are more sensitive to medications then others I am going to go through the proper treatment for a Betta. Some fish are more delicate (like scaleless fish) and may need a modified form of treatment.
Trophont Phase- [approx 4 days] The Trophont is the adult protozoan that is feeding on your fish. This is what you are looking at when you see the “granules” attached to your fish. The parasites are not susceptible to treatment during this phase.
Tomont Phase- [approx 1 day] The Tomont occurs when the Trophont [above] releases from your fish and falls away. It then begins to divide hundreds of times in your tank but is too small to be seen by the naked eye. To the inexperienced aquarist it may appear that your fish is healed but the protozoan is still not susceptible to treatment during this phase. It is just reproducing and will attack your fish more severely if not handled in the next phase.
Thernont Phase- [approx 2 days] This is the phase where the microscopic parasites are free swimming around your tank and are most vulnerable to treatment. While they are looking for a host it is important to be medicating your tank. With proper treatment the parasites will die off during this stage before feeding on your fish and starting the cycle again.
To treat your betta it’s important to know that the Ich parasites are contagious and the medication is fairly strong. It’s best to move your fish to a hospital tank if he has tank mates so as not to expose them to more parasites or unnecessary medication. The medicine used may kill helpful nitrifying bacteria so activated carbon filters should be removed during the treatment process.
The Ich parasites thrive in cooler water below a temperature of 78˚F [25.5˚C] so slowly raise the temperature in the tank to around 80˚F – 82˚F [26.6˚C – 27.7˚C] over the next 24 to 48 hours.
Carefully follow the directions on the medicine bottle remembering to perform 25% water changes before each dose and to continue dosing for several days past the visible signs of the disease.
Since fish generally become infected due to stressors it’s imperative that you determine what may have caused the fish to get sick to begin with. Check your water parameters and make any corrections as needed.