Everyone does it their own way. Depends too on the size of the pond. For instance, with a 3,000 gal pond some people just add the water from the hose because the chlorine is diluted to a point it won't harm the fish.

However, I have a 160 gal pond, so I don't want to just add city water to the pond. I address this two ways. Sometimes I add Stress Coat to dechlorinate the water. I put the water in a 20 gal blue tub with Stress Coat and let it sit for a day then siphon it in. Sometimes I use a dechlorinator filter that is made for campers and just add it directly to the pond or stream.

Hopefully others will chime in with their methods. You should find one out of all of them that fits your lifestyle.

Anne

Not a silly q at all; how many gals is your pond?

I follow the rule given to me several years ago that says that if I am adding water equivalent to more than 20% of the total volume of the pond, I add dechlorinator- otherwise, don't worry about it.

We do about a 10% to 15% water change every week, and never add dechlor; I'd think that if all you're doing is topping off the pond, and there is no real big issue with a leak, you'd be fine just topping it off without adding dechlor (of course, assuming you're adding less than 20% of the water to the pond).

Hi
A good way to determine what is necessary is to know what's in your tap water Municipal water supplies vary considerably this also varies from month to month.
Besides chlorine many add chloromines and ammonia to make the treatments more stable over longer periods.
I've always followed the "10 percent " rather than 20.
rule. But dechlors also neutralize heavy metals. If they are a problem in your water supply you'd want to consider that also. Certainly dosing the replacement water won't hurt anything though I only do it at over 10 percent without problems.for many years. have even followed that guideline with small aquariums . gary

My pond is (I think) about 5500 gal. It is 16x24 feet and 3' feet deep in the center with a 6inch, 1' and 2' foot deep shelves around the outside.

To answer your original question, you add dechlor for the amount of new water you are adding.

Pecan, my water garden is a minute fraction of the size of yours I can haz energizer gardener battery plz? so this might not work for you. But then again, anybody who can just whip out a stained perfect deck on a Saturday night can probably tackle a siphon system!

On average, over any given 7 day period; I pull 10-20% of my pond water out to water/fertilize my veggies. Then I top the pond back up with a shower head on the sprinkler. I'm usually only pulling out less than 5% at a time.

If you had some kind of siphon system, and did a 10% (550 gallon) water change - de-cholorinating 550 gallons outside your pond could be interesting. You could reverse the siphon system and siphon from the irrigation ditch through a debris filter into your pond. I would assume at least. Or make some type of ditching/gate system to open your flood water to your pond.

~dianne

PS - and your pond is just beautiful. Can't wait to see more pics.

Oh, and we have friends in Utah. They get some lovely photos in the late afternoon when they are flood irrigating their yard and the Belgian's are out playing in the water.

add enough for the amt of water you are adding

Using a sprayer to add the water dissipates the chlorine (instead of straight from the hose) Not sure how practical that is for a large pond though.

Have been told that you can add 10% without dechlorinator. I feel I must add this warning for readers though: be sure you never walk away from the pond when you are adding water straight from the hose. I almost killed my fish this way - got sidetracked and by the time I remembered, they'd gotten a nearly lethal dose of chlorine.