In most cases, adding declor is not a requirement. Aerating the new water take
higher priority. I recently added 75% of tap water to my old pond without any
declor. However, I did add a bit of Potassium Chloride to reduce chloramine
effect.

kc wrote:

Well, I just went outside to discover my poor little goldfish swimming
around in 12" of water instead of 2 feet or more--as it is there are too
many goldfish (had babies) for my 1,000 gallon pond--probably about 24....I
inherited this pvc or rubber lined pond with my house and don't even know
where to start to find the leak, but in the meantime, I need to replace the
water--can I safely add it back in if I use appropriate declorinator?
Thanks for your help.
Kirsten