Sally,

We really need some additional information. What is the pH, KH, ammonia,
nitrite readings as a minimum, nitrate if you can furnish it? What were the
symptoms (flashing, hiding, gasping, sores, etc.)? What type of water, well
or city, and if city do they chlorinate or chloramine treat? What
treatments if any other than water changes have you done? Any other
pertinent info like insecticide spraying near pond, fertilizer, or other.
--
RichToyBox
http://www.geocities.com/richtoybox/pondintro.html
"Sally" wrote in message
om...
We've had koi for about 8 years, and they're suddenly dieing. We
pumped out the pond, and put in fresh water. After waiting about a
week, we put in a new koi. It's been about 3 weeks. He appeared to be
fine, but we just found him dead. We made a mortar repair on the
waterfall in the spring, but we've done that before and never had any
problem. Also, we've done a complete water change since then. Any
ideas? We're puzzled and could use your help.