I have not had Ich in my 5ft tank for well over 15 years. Where I live it is extremly prevelent during the colder months where it comes via the water supply.

My method is to store the water for 7 days. As there is no hoast the Ich parisite dies. BUT bewarned it is not known how long it can lay in a dorment stage before it fully develops. What is known the colder the water the longer it survives.
Prevention is the best.

"White-spot" Parasite, Ichthyophthirius multifiliis

This disease is easy to recognise, as the skin of the infected fish becomes covered with white spots, each the size of a pinhead. Each spot represents the site of one, or sometimes two, parasites. All parts of the body gills, may be attacked.

The causative agent is named Ichthyophthirius multifiliis. It is a spherical and large by protozoan standards, measuring up to 1mm in diameter. Short, hair-like processes known as cilia are spread densely over the surface. A horseshoe-shape nucleus is also present which is clearly visible under the microscope.

By the means of the cilia the parasite rotates vigorously and burrows into the surface layer (epidermis) of its host. It feeds on skin cells and surface debris. The burrowing action causes a local irritation and the epidermis grows across the parasite to enclose it, thus forming a "White Spot"

Reproduction occurs away from the host. After maturing in the skin, which takes a few days to three weeks, depending on the temperature, the parasite bores out, swims away and comes to rest on a submerged object such as a stone, or plant. Here it forms a jelly-like cyst within which a series of rapid cell divisions take place. In a few hours, several hundred daughter cells or swarmers, are produced, which break out of the cyst to find a new host. Alighting on the skin, they burrow in to recommence the life cycle. If they fail to find a host within three to four days, they perish.

Symptoms
If the protozoan is introduced into a tank containing healthy fish, little harm may occur, other than a fleeting infection with a few parasites. If however, the fishes are already weakened for some other reason, e.g. lack of oxygen, the parasite will quickly cover the whole body surface, causing irritation and opening up wounds for secondary infections. The host mobility may become affected. In sever cases, death may result.

Prevention
If white-spot appears in an otherwise healthy tank, the parasite "must" have been introduced either as an adult on a newly acquired fish, or as the cyst form on, for example new stones, a plant or even added water. The only certain method of prevention, is to quarantine all new stock, including stones, plants etc; preferably in water at a temperature of 77F. Allow one weekÂs quarantine.

Treatments
There are too many treatments today to recommend any specific one. Many can be bought easily at aquarium outlets.

Or you can just use aquarium salt in freshwater tanks.

I cannot use salt in my planted aquarium.I also have fish which do not tolerate salt.Although this is acceptable for some setups.

I have used high temps(85) for a few days without salt or meds and have had success with stopping it.

crank the temp to 82 to 85 degrees and leave it for a few days....wont do damage to plants unless they are heavy CO2 feeders and/or are extreme cold water plants like spadderdock. gradually, over the course of a few days, lower it back to normal....fish should be fine.