| Activated charcoal filters are not very effective in removing cholrine. The absorbtion factor is almost zero after a few minutes use. It is more advertising hype than efective.
I used to own a tropical fish importing firm. Chlorine was a major problem when you used 10,000 gallons of water a day (New Jersey water, where the chlorine was treated with ammonia to remain in water longer). All the major manufacturers sold activate charcoal filters, but they would admit to me their tests showed a mere 15 minutes exposed to air saturated the charcoal. It did have value for growing helpful bacterias, but not for removing chlorine.
sodium thiosulfate dissolved at the rate of 1 ounce per gallon for a stock solution is an immediate removal of cholrine. Use ONE DROP of the stock solution to neutralise the chlorine in one gallon of water. The reaction is almost instantaneous. Over the years, I put over 8 million dollars of fish in water treated this way so it works.
Sodium thiosulfate was the black and white photographers fixation solution to preserve black and white prints in darkroom work. You may still be able to find it in some better camera stores or certainly in a chemicals supply compant.
Leaving it out overnight is effective for all but the most heavily chlorinated water when fortified with ammonia. New Orleans water from the Mississippi would kill fish even after a week of airation.
Most parts of the country the level of chlorine is low enough not to effect plants when watered directly from the tap. Chlorine is also removed with airation and if you water through a sprayer it removes much of the chlorine.
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jerry  |