My understanding from reading all these wonderful references on this forum and from all of these wonderful people is that vitamin C is an anti-oxidant while Iodine is an oxidant. That particular effect may be what you want for the water; while it may not be what you want for this Iodine therapy. I suppose that the Iodine would be added first in order to destroy the bad stuff; then vitamin C would be added to nullify the effect that iodine would have on your body (as an oxidizer).