Curses on rain rot indeed...I had a flare-up again this year. I went on a 3 day vacation, come back, and BAM; scabs up and down both sides of his neck and one flank. Hope its not going to become a regular occurrence
I usually just use m-t-g, but a friend recommended Micro-Tek to me ( this stuff:
http://www.eqyss.com/skin_problems.asp ). I decided to try it out and the problem cleared up immediately after one bath and 2 days of the spray on the problem spots. Granted, I got it early too.
The downside is the price...its expensive stuff. $50 for the shampoo and spray together. But I was very happy with the results and hopefully I won't have to use it more than 2-3 times a year *fingers crossed*
If he's only having a problem on his blaze, I would question whether it is actually rain rot as well. Are you just getting skin flakes or actual scabs?