Well there is only one sure way to get rid of ick...and that is leaving your tank fishless for 6 weeks. This is also the method that some of us cant really do since we dont have space to set up a q-tank or a h-tank, cant catch all the fish to place them in the tanks or its just better to let them fight it of on there own.
Its possible to rid ick with the use of a UV, but this can take time since the parasite needs to be in their free swimming stage and has to go throu the UV (at a very slow speed to be killed) before finding a host. It can take time for this to happen since once the first stage of ick falls of the fish (this is where we all think that we have cured the fish) to reproduce, then it will go out and seek a host and most of the time they will do this at night when the fish are sleeping, close to the bottom of the sand, thus a large percentage of the parasite finds a host before elevating to a point where the UV can suck them in and kill them. This cycle can continue for many cycles until the fish die, the UV has been able to kill all the parasites or the fishes just simply get ammune to the parasite. If its the later, sometimes you will have another ick outbreak when you introduce a new fish, thus affecting him the worse. UV's cant cure a fish with ick but will kill all parasites that enter the UV.
Kick ick has been used by many and has debates on weather it actually acomplishes what it claims. We dont know if the Kick Ick worked, helped the fish fight of the parasite, or if the fish just fought it of on its own which many fishes can do, depending on how long they have been in the tank and if you have fed them the specific diet they requier to be healthy. A healthy fish will defeat this deadly parasite.
Garlic has been know to have some kind of ability to give fishes super powers in a way. It can boost their imune system through the roof, and in many cases will help them fight off the parasite, Some say the garlic will cloak the fish so the ick cant find them when they are in search of a host. No scientific data exist to prove this, but it cant hurt. I dont think garlic is a cure, more like a shield, it will help the fishes fight the parasite but you still need to keep good husbundry practices.
There been reports of people using ginger to make the fish slime coat thicker so the parasite cant attach to them. Why anyone would dose ginger in a tank is beyong me but the same goes for the garlic. Theres always 1 person whos willing to try and experiment with something new.
Copper is a sure way to kill and cure fishes from ick, but it can also killl the fish, kill all inverts and the tank you dose it in will never be reef rerady as the copper will always be in there. Copper is dosed in a seperate tank that we use for the purpose only. Again not the easiest thing to do since you have to catch the fish and set up the tank and what not. All this is just more stressfull for the fish. If the ick is discovered very early then its a good way to treat since they are still composed enough and will handle the move better.
Hypo is a safer way to treat ick. But it takes time. You just cant take a fish and dump it in a tank with a SG of 1.008. Must be done slowly. It is effective and has been proven many times to work. Again early detection is the key to success.
In all I just like to let them ride the wind. I trust that I have done a good job of feeding them and to accomidate their habitat to be as stressless as possible. Feed the garlic and try to keep them eating. If you see that they arent eating and they are just plain looking bad, its time to do the hypo or copper and wish for the best. In this stage they will be easy to catch as they wont have the energy to put up a fight.