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Name:  tom hammargren
Status: N/A
Age: N/A
Location: N/A
Country: N/A
Date: 1999 

I want to remove chlorine from tap water so plants I water with the tap water are not harmed by the chlorine. Is there a safe, cheap, and effective chemical I could use?

You can boil the water for fastest results but a real waste of energy. You can just leave water on the shelf for a few days or place in the sun for speedier results. A test kit from a pool supply store may help you decide if the Cl has been depleted enough. This treatment will allow volatile molecules (like chloroform too) to dissipate but not larger molecules (eg., PCBs). Good Luck!

michael b lomonaco


Do yo have any evidence that the chlorine is actually harming the plants?


To remove chlorine quickly and easily, go to a fish supply store and purchase dechlorinator. The cheap brands are as good as the expensive ones. The cheap brands are very inexpensive. To answer Ric's question, chlorine in tap water is known to cause chloridosis, or yellowing of leaves. Some water treatment facilities are using an aminated chlorine that is not as easily removed by allowing the water to sit out. I strongly suggest the use of commercial dechlorinator.



I'm not sure that I buy the assertion that chlorine in tap water is present in sufficient quantities to cause chloridosis. Using the dechlorinator you mention can actually inadvertently remove other trace mineral salts needed by plants.

Naturally my note above is THEORY; this would be a good opportunity to experiment by using water from various sources, including the dechlorinated variety you mention. Such an experiment can include data on water pH, and iron concentration, which are the two most common causes of yellowing in plants. Naturally this experiment can be made as complex as desired. One thing you might do for some info is to get a bottle of a commercial fertilizer and try to determine the chlorine concentration it would have when mixed with regular tap water according to its directions. You can comment on whether you think the level of chlorine due to the fertilizer is much affected by any chlorine in the tap water or not.

Tom, again, I am curious as to whether or not you have any evidence that the chlorine is actually harming the plants?

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