1) Return the fish since your tank is not cycled. Using fish to cycle is unnecessary and will cause them long term health problems, if they survive in the first place.
2) Read here for several methods on how to cycle a tank without using fish: http://www.tropicalfishkeeping.com/f...m-cycle-38617/
3) Ich needs a host to survive, cycling a tank takes usually 4-8 weeks to complete. No need for meds, it will solve itself in an empty tank. Just jack the tanks heater up to the low 90's (if no fish or live plants) to speed its life cycle up.
With Ich, an entire tank will be infected, including the filter. Removing the filter for a couple days then putting it back in will accomplish nothing. Changing any percentage of the water will change nothing. Ich is a parasite that attaches to the fish and starts to feed. It is immune to medications in this stage. When full, it will detach and drop to the bottom of the tank (or decorations or get sucked into the filter) and will begin to multiply by the hundreds/thousands. Again, it is immune to medications. When finished, it will become free swimming and this is the only time it can be killed by medication. If it can't find a new host ... it dies.
If your filter has carbon, dispose of the carbon but leave the filter pad so you don't loose the bacteria. Do not save the carbon and re-use it. The carbon will be infected, and can not be left in the tank if using meds as it will absorb most of them. Follow the directions on the package of the meds.
The speed of that cycle is dependent on temperature. The higher the temperature, the faster the cycle. If you are treating fish, you want to get to at least 86 degrees if the fish do not show signs of stress from the elevated temperature. If they do show signs of stress, lower it until they don't, but get it as high as you can.
Ich is present pretty much everywhere, and can be more or less dormant for months. Fish with a healthy immune system can easily fight it off and not show any signs. But being in an uncycled tank causes extreme stress, and stress weakens the immune system and invites disease.