Thanks much. I couldn't say what acid ratio I use. I heat my water just a bit and add two good size chunks of ferric. I use solid ferric chloride that I have left over from my old job as a chemist. Two ping pong size chunks with a warmed gallon of water. The solid ferric is easier to use and it was free. Gotta love that. The company had to pay for chemical disposal, so they were happy to give me a ton of ferric, etc.
liontribe