Dechlorinator

[rdd1952]

I was just reading a question in the Beginners section, and it made me stop and think about this. From all I have read, dechlorinator works almost instantly. We fill a bucket with water, squirt some dechlor in and the chlorine is gone. What about the chloramine? How long does it take the dechlor to break the chloramine bond?

If it is instantaneous, then obviously, the newly released chlorine would be removed but if it takes time, will there be dechlor left to act on it? I've never heard this mentioned before and in a quick Google search, I didn't get an answer. I did find one article that basically said that after the bond was broken, that thiosulfate would quickly remove it. Thiosulfate being an ingredient of our dechlor, if it is always present in the tank to do that, why would we need to continue to add dechlor every time we do a water change other than to replenish what we have removed with the water?

Does this question make any sense or is my aged brain trying to think too much?

 

[Bignose]

I am sure the thiosulfate gets broken down over time. There are bacteria, especially in the oxygen-poor zones that would use sulfur as an energy source. If your water is acidic, thiosulfates are definately not stable:

S2O3(-2) + 2H+ --> SO2 + S + H2O

The SO2 will leave the top of the tank as a gas, the S is a sold and will precipitate at the bottom of the tank or react with something else (like the bacteria using it).

Thiosulfates also can react with chlorine (which is hoe declorinators work) and are consumed in the process. They aren't going to hang around forever, and dechlorinator is awfully cheap, so I'm of the option, why risk it?

 

[rdd1952]

I definitely wouldn't risk not using dechlor but back to part of the original question, how long does it take for the chloramine bond to be broken by a dechlor like Prime or Stress Coat? I'm assuming that the thiosulfate will not get broken down that quick.

 

[Bignose]

The chloramine bond is broken very quickly -- for all purposes instantaneously. Dechlorinator, all the steps of the wide range of products, works very fast.. Cloramine is broken fast, the chlorine gets neutralized fast, the ammonia gets converted to ammonium or some other bound up molecule fast. You can give the water a swish or a stir if you are really worried about it, but there is enough mixing from pouring the water into the tank to ensure everything is reacted already.

 

[rdd1952]

That's pretty much what I thought after I had time to really think about it. I know some people suggest using a dechlor like Prime since it neutralizes ammonia so that when the bond is broken, the ammonia is non-toxic but I have always felt that we are dealing with such a minute amount that it wasn't really an issue and could quickly be processed.