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Ok, going beyond that some of you don't like to use carbon. I heard that if you boil carbon every other month it is just like putting new carbon back in the filter. Is this true? Can I keep using the same carbon if I boil it periodically?
 

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I would imagine there has to be a way to "reactivate" the carbon so it works again. The way I have seen to do it is to bake it in the oven for hours on end at very low temps. Boiling it should remove some of the stuff from the carbon but I am not sure if a single boil session would remove even a majority of the nasties.

As for using carbon, there are a lot of people that swear by it. And it is only actually effective for about 3 weeks unless your tanks are very understocked and your water is extremely clean and soft. No chlorine, chloramine, heavy metals, odors nor anything else.

Just be careful whatever you do with activated carbon. I do not know the science behind it nor much about it but I have heard you can relase carbon dioxide/monoxide in massive amounts if you heat it wrong or too hot. How much truth there is too it I don't know but better to know.
 

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ok i am going off memory i am sure ill find it sooner or later but the carbon has to heat up very hot i think 450+ with pumped in o2 to reactivate that carbon.
Almost. It's got to be heated up to 900 degrees in an oxygen free environment.
 

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NO, you can't regenerate activated carbon. You can extend it's use life slightly by briskly rubbing it together (in a pouch) while rinsing to expose new surface areas.

Contrary to what some believe, activated carbon does not release impurities it has adsorbed, however, once it has adsorbed all the impurities that it can, it becomes useless for that purpose in the filter.

The effective use life for carbon varies relative to the amount of carbon and the condition of the water. A good pouch of carbon placed in a neglected tank could reach capacity in a couple of days. A sprinkle of carbon inside a filter cartridge pad could last a couple of hours! If there's a fair volume of carbon placed in a fairly clean tank, it could remain effective for up to a month.
 

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I just noticed that this thread goes back to 2007 :shock:

It's still useful information so once in a while it's good to revive these old ones that didn't get much activity initially.
 

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NO, you can't regenerate activated carbon. You can extend it's use life slightly by briskly rubbing it together (in a pouch) while rinsing to expose new surface areas.

Contrary to what some believe, activated carbon does not release impurities it has adsorbed, however, once it has adsorbed all the impurities that it can, it becomes useless for that purpose in the filter. .
You, as in the consumer, cannot refresh the carbon because we do not have the means to do so, but YES it can be done, as I explained on my previous post.

Yes, carbon DOES release things it has adsorbed back into the water. It is not a true chemical reaction that takes place. Carbon works via the Van der Wals force. Things that have an affinity for the carbon are drawn into it and are locked up at a receptor site. Once the receptor sites are full, new things with a higher affinity will knock out things with a lower affinity, which are then released back into the water. Some people, particularly in the discus community, think that carbon can spontaneously release everything, and that is just flat out wrong as it takes some very extreme conditions to do so.

I have two chemists in the family that I have talked with at length. That is the science of AC.
 

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Jaysee, I merely reported what experts have documented. I believe I wrote "No, YOU can't regenerate activated carbon."... Meaning the original poster, not that it couldn't be done in a high temperature vacuum chamber.
I believe that the adsorbtion by activated carbon does not likely support your theory of element replacement. It seems more likely that once adsorbtion has reached capacity, there is no surface capable of entrapping any other elements, causing previously trapped elements to be released. Again, no disrespect to your family, but I merely reported what many experts have documented in several different publications.
 

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It's not my theory. Which publications do you speak of?
 

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You talk about these experts and publications but can't provide more direction than that???

I'll stand by the words of Physical Chemists.
 

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One example - Activated Carbon in the Aquarium

"Does Activated Carbon De-Adsorb?
You may hear that once activated carbon has reached its capacity, it will start leaching some materials it previously adsorbed back into the water. This is not an accurate claim. Although technically possible, to de-adsorb requires changes in the water chemistry that simply do not occur in the aquarium. "
 

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wow, about.com - a highly respected publication. Written by an avid fish keeper and photographer. That HARDLY makes her an expert on activated carbon, or anything related to chemistry....
Again, that was just one example. I've read this over and over in many publications. The notion that once at capacity, activated carbon begins releasing all that it's adsorbed is a myth used by many to discredit it's value in water purification.
I guess we'll have to agree to disagree.
End of discussion.
 

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Well, you can believe the fish experts and I'll believe the real experts.
 

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Again, that was just one example. I've read this over and over in many publications. The notion that once at capacity, activated carbon begins releasing all that it's adsorbed is a myth used by many to discredit it's value in water purification.
I guess we'll have to agree to disagree.
End of discussion.
Based on the quality of information cited in this thread, I don't think anyone should be obliged to agree to anything.

I also think it unneccesary to "end a discussion" simply because you can't locate your sources.

Reading the oft-referred-to citation (which I found cut and pasted in at least two other generic sources) I note that wide swings in pH level can cause de-adsorption. I would like to know what level of change in pH is necessary to accomplish de-adsorption. For example, if a person suddenly decided to convert a marine tank to a planted tank and the pH dropped from 8.4 to 6.0, would that do it?

This is the kind of thing alluded to on marine forums with respect to copper adsorbed by calcareous materials, and one of the reasons that use of copper in anything but a quarantine tank comes with its own set of caveats. But if it's true that very low pH could cause a cleansing of activated carbon, shouldn't we be telling our friend verbosity to quit boiling the stuff and use some sort of acidic formulation? Not that the de-adsorbed carbon would ever be safe for aquarium use. . .
 

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Again, that was just one example. I've read this over and over in many publications. The notion that once at capacity, activated carbon begins releasing all that it's adsorbed is a myth used by many to discredit it's value in water purification.
.
Let's stay on point here. No one is talking about the carbon releasing ALL that it has adsorbed. That's been established as a myth, yes, because it is one - carbon will not spontaneously dump everything. That claim was never made in this thread, however. The point of discussion, up to now has been whether or not things can be bumped out.

There is great shortage of ACTUAL science in fish keeping. There is a lot of uncited information (like in the link) that gets copied and pasted and parroted. This is something that is pervasive in the hobby, across all categories. Just because you read something over and over (in fish keeping publications?) doesn't make it true, especially when one source is just copying another. This occurs in fish profiles ALL THE TIME, and it doesn't end there.
 

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Based on the quality of information cited in this thread, I don't think anyone should be obliged to agree to anything. I also think it unneccesary to "end a discussion" simply because you can't locate your sources.
My 'end of discussion' remark was intended for Jaysee to communicate a reluctance for further debate for the sake of argument. I saw no reason or purpose to further produce documented evidence that the earth was round, regardless of what some relatives believe.

Here are a few more examples:

Using activated carbon (charcoal) in the aquarium
Activated Carbon in the Aquarium
Using Activated Carbon in the Aquarium - Algone.com
Activated Carbon In Aquarium | Aquariums Life
Activated Carbon - The Free Freshwater and Saltwater Aquarium Encyclopedia Anyone Can Edit - The Aquarium Wiki

Perhaps these sources are all wrong and/or just copied the myth around, but nowhere do I find ANY documentation that de-adsorbtion is possible except, as you point out, in extreme cases of a pH shift so great it could not exist in an aquarium with any surviving fish.

However, before suggesting that the OP soak the carbon in vinegar, it might be better to just throw it out and start fresh.
Or better still... don't use it at all or certainly don't use it regularly. It is understood that activated carbon removes impurities. But it doesn't discriminate and some 'impurities' (including dissolved organics) are important elements for beneficial bacteria, plants and fish.
We might further argue that the glass box aquarium can't truly be compared to waters in nature. However, emulating and leveraging natural conditions in the aquarium would seem to result in a more healthy environment.

Okay, so you called me out and made me go back on my word. Time now to move on to more exciting topics :-D
 

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My 'end of discussion' remark was intended for Jaysee to communicate a reluctance for further debate for the sake of argument. I saw no reason or purpose to further produce documented evidence that the earth was round, regardless of what some relatives believe.

Here are a few more examples:

Using activated carbon (charcoal) in the aquarium
Activated Carbon in the Aquarium
Using Activated Carbon in the Aquarium - Algone.com
Activated Carbon In Aquarium | Aquariums Life
Activated Carbon - The Free Freshwater and Saltwater Aquarium Encyclopedia Anyone Can Edit - The Aquarium Wiki
Relatives with PhDs. None of the people that wrote any of those "articles" are experts on anything more than MAYBE keeping fish. You should step outside the fish keeping world from time to time....
 
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