Here is a photo of a dosing tank like Dick describes....
http://www.koi-bito.com/forum/attach...thingy.....jpg
You will need about 2 ounces of muriatic acid (31% HCl) per 100 gallons. Sodium bisulfite is usually cheaper than muriatic acid, but there is more chance of some weird side effect.
You have some funky water if the pH is 9.0 and KH is 170 ppm. There may be a lot of potassium chloride or magnesium chloride. When you send off a water sample, ask them to quantify the different bases. Also get them to do a heavy metal profile because when you fix the pH the heavy metal toxicity may become an issue.
If pond-grade koi is not an option, then there is probably a reverse osmosis filter in your future.
-steve