We've always used 7%, but I saw 5% in a tack store the other day. After I used 7% this year, some of my foals seemed to be having a reaction of some sort to it. Then I realized, my hands being covered with iodine since some of the zigged when I zagged, the stuff smells REALLY strong, and maybe the reaction they seem to be having is to the smell. Just about burns your eyes. Maybe it's time to rethink this 7% stuff. Never happened before tho.
But I wouldn't use 10%. JMHO. I think I'm going to go buy 5%. I've heard of the use of something called Novasol or Novasal or something like that, but I can't find it in any local tack shops & we have 4 nearby.
I'd like to hear other folks thots on this too.