Question
I am wondering what would be the best way to perform water changes on a 400 gallon pond. I am concerned about replacing 25% each time due to chlorine/cholramine. I want to do changes each week but get concerned about killing my biological filtration and hurting my Koi.

Answer
Hi Greg,
Why don't you change 10% twice a week and let the water splash into the pond rather than trickle straight in, this will disperse the chlorine in the water and should have no adverse effect on your filter.
George.
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