Ich in a planted tank is a bit harder to deal with. Use a combined approach:
Raise the temperature over 85*. Many strains of Ich cannot live at this high temperature. Make sure to increase the aeration. Warmer water holds less oxygen, and the fish may have Ich in their gills, further compromising their breathing.
Frequent (daily) vacuuming. You do not have to dig into the substrate. You are trying to vacuum the fallen Ich off the floor of the tank before they can reproduce. They also land of leaves, rocks, driftwood... this sure complicates the vacuuming, but do your best.
UV sterilizer. The problem in a planted tank is the low-flow areas that will not get treated. Ich can reproduce in those pockets.
Move the fish (all of them) to a hospital tank for treatment, and leave the planted tank bare for at least a week (longer, really, treating the fish will take longer).
The very day you move them you have created a break in the life cycle. Take advantage of that and vacuum the floor (bare bottom tank) daily so the Ich never has a chance to re-infest the fish.
Use a UV sterilizer, too, so that any that do hatch can be killed before they find a host.
The planted tank without fish cannot have live Ich after about 48 hours, if the temperature is high. If you leave this tank in the mid 70s Ich could live for several days, but not a week.
Once you remove the fish, the only thing left in the aquarium are the non-feeding Tomont part of the life cycle , and at 75 deg they need to find a host within 3 days. The cooler the water, the longer they last without a host - without a heater in the tank you should probably give it a week to be sure. By keeping all livestock out of the tank for enough time, this part of the problem will take care of itself. water changes, of course, only helps.