DD DDD wrote:
I just added a auto water pond filler. Is ther a Chlorine and heavy
metal garden hose filter? I sometimes put my backflush on to clean my
filter. I let it run in the garden then pour garden hose water in. so
far no problems. Bur if I ever do a 10-20% water change (300 gallon
pond) I dont want anything bad to happen. How much of a water change can
I do without adding declor? I can no longer lift buckets of water that i
declor to pour in the pond. Is it safe to add some tap water without
hurting the fish? I was hoping I could just backflush about 30 gallons a
week the the auto filler would fill it. Please let me knowThank again

I recall reading in "Doc Johnstons" book that gill damage due to
Chlorine is cumulative. That would suggest that there is no "truely
safe" level of untreated city water to add to your pond.

Cheers.