So my horse has the most beautiful, full, shiny tail you will ever see. But that's only on the top layer. If you look through his tail, it goes from a shiny chestnut, to a dull, gray, sticky, dandruff-filled, disgusting mess. What do I do?
Perhaps it's a reaction to all the shampooing and conditioning then? I'm just taking stabs at the wind here, but it's possible. You can stop putting any product in his tail for a while to see if it makes a difference. Or you can try an anti-bacterial or anti-fungal shampoo. I don't think either would be harmful if it wasn't bacteria or fungus related.
http://www.doversaddlery.com/healthy...1-2225/cn/151/ This stuff. Just try it. We use it on all the horses and it leaves them with a beautiful mane and tail all the way through. Its a leave in spray that you do 1 part of the stuff and 8 parts water so it lasts a long time.
This may sound crazy, but find some oatmeal dog shampoo for dogs with sensitive skin. My pony's mane was all dandruff-y and very coarse so I decided to use my puppy's shampoo on her and it worked like a charm. It's also very cheap and easy to find.