Water Conditioner, Is It Worth It

[Bignose]

I actually doubt that leaving the chlorine in the water is a significant effect at all. If the water company used chlorine gas, that will leave the water in a very short amount of time. And, if the water company used chloramine, the ammonia oxidizing bacteria can use chloramine as a food source. And, given the very large number of filter bacteria that a cycled tank has, the chloramine is going to be consumed very quickly. Either way, the chlorine in the water doesn't stay in the water very long.

 

[fishyfeet]

would chlorine left in the water supply not kill off bacteria in your filter, hense not rinsing filter media out in tap water, di

 

[andywg]

would chlorine left in the water supply not kill off bacteria in your filter, hense not rinsing filter media out in tap water, di

While not scientific, the number of people who keep fish tanks successfully without any dechlorinator suggests that the chlorine levels are not a major problem.

Further, consider how long it takes for us to get a bacterial colony of the size we want. Assuming a 20 day cycle and a doubling of the colony every 24 hours then we have a colony some 1,048,576 times greater than the levels of bacteria found in the tap. As a result the amount of chlorine found in a water change will not be enough to completely wipe out the colony.

 

[cheesy feet]

No conditioners for me, never had any problems...Prices are ridiculous for them anyway.

 

[Schmill]

I thought it was not the damage to the bacteria that the dechlors were used for, but because of any 'gill burning' etc that the chlorines might cause to the fish themselves?

 

[fishyfeet]

well i think your wrong,

Chlorine is a greenish-yellow gas that dissolves easily in water. It has a pungent, noxious odor that some people can smell at concentrations above 0.3 parts per million. Because chlorine is an excellent disinfectant, it is commonly added to most drinking water supplies in the US. In parts of the world where chlorine is not added to drinking water, thousands of people die each day from waterborne diseases like typhoid and cholera.
Chlorine is also used as a disinfectant in wastewater treatment plants and swimming pools. It is widely used as a bleaching agent in textile factories and paper mills, and it’s an important ingredient in many laundry bleaches.

Free chlorine (chlorine gas dissolved in water) is toxic to fish and aquatic organisms, even in very small amounts. However, its dangers are relatively short-lived compared to the dangers of most other highly poisonous substances. That is because chlorine reacts quickly with other substances in water (and forms combined chlorine) or dissipates as a gas into the atmosphere. The free chlorine test measures only the amount of free or dissolved chlorine in water. The total chlorine test measures both free and combined forms of chlorine.

If water contains a lot of decaying materials, free chlorine can combine with them to form compounds called trihalomethanes or THMs. Some THMs in high concentrations are carcinogenic to people. Unlike free chlorine, THMs are persistent and can pose a health threat to living things for a long time.

People who are adding chlorine to water for disinfection must be careful for two reasons: 1) Chlorine gas even at low concentrations can irritate eyes, nasal passages and lungs; it can even kill in a few breaths; and 2) The formation of THM compounds must be minimized because of the long-term health effects.

Less than one-half (0.5) mg/L of free chlorine is needed to kill bacteria without causing water to smell or taste unpleasant. Most people can’t detect the presence of chlorine in water at double (1.0 mg/L) that amount. Although 1.0 mg/L chlorine is not harmful to people, it does cause problems for fish if they are exposed to it over a long period of time.

More info here - http/weblife.org/humanure/chapter5_8.html

 

[raptorrex]

well i think your wrong,

Chlorine is a greenish-yellow gas that dissolves easily in water. It has a pungent, noxious odor that some people can smell at concentrations above 0.3 parts per million. Because chlorine is an excellent disinfectant, it is commonly added to most drinking water supplies in the US. In parts of the world where chlorine is not added to drinking water, thousands of people die each day from waterborne diseases like typhoid and cholera.
Chlorine is also used as a disinfectant in wastewater treatment plants and swimming pools. It is widely used as a bleaching agent in textile factories and paper mills, and it's an important ingredient in many laundry bleaches.

Free chlorine (chlorine gas dissolved in water) is toxic to fish and aquatic organisms, even in very small amounts. However, its dangers are relatively short-lived compared to the dangers of most other highly poisonous substances. That is because chlorine reacts quickly with other substances in water (and forms combined chlorine) or dissipates as a gas into the atmosphere. The free chlorine test measures only the amount of free or dissolved chlorine in water. The total chlorine test measures both free and combined forms of chlorine.

If water contains a lot of decaying materials, free chlorine can combine with them to form compounds called trihalomethanes or THMs. Some THMs in high concentrations are carcinogenic to people. Unlike free chlorine, THMs are persistent and can pose a health threat to living things for a long time.

People who are adding chlorine to water for disinfection must be careful for two reasons: 1) Chlorine gas even at low concentrations can irritate eyes, nasal passages and lungs; it can even kill in a few breaths; and 2) The formation of THM compounds must be minimized because of the long-term health effects.

Less than one-half (0.5) mg/L of free chlorine is needed to kill bacteria without causing water to smell or taste unpleasant. Most people can't detect the presence of chlorine in water at double (1.0 mg/L) that amount. Although 1.0 mg/L chlorine is not harmful to people, it does cause problems for fish if they are exposed to it over a long period of time.

More info here - [URL="http/weblife.org/humanure/chapter5_8.html"]http/weblife.org/humanure/chapter5_8.html[/URL]

it would be valid, if we could find anyone who was killing their fish, because they were not using it!! or indeed show any benefits from using it.

 

[fishyfeet]

trouble is if the damage is minimal, the fish cant say that feel ill and def dont show it as it would attact preditors and it may take sometime before the fish actually dies and even then the its always questionable what the fish died from. di

 

[raptorrex]

trouble is if the damage is minimal, the fish cant say that feel ill and def dont show it as it would attact preditors and it may take sometime before the fish actually dies and even then the its always questionable what the fish died from. di

yes, but none of my fish are dying, and its been over 12 months since i stopped using it. and my story is far from unusual. but there is nothing wrong with using it, as a precaution. its just I and many others don't!

remember, its not that long since water changes were frowned upon! seems daft now, but knowledge and techniques move on.

 

[aaronnorth]

People who are adding chlorine to water for disinfection must be careful for two reasons: 1) Chlorine gas even at low concentrations can irritate eyes, nasal passages and lungs; it can even kill in a few breaths; and 2) The formation of THM compounds must be minimized because of the long-term health effects.

We are not adding any Chlorine to the water, it is already in the water but at safe levels, so the above points are useless to this topic.

 

[Bignose]

Although 1.0 mg/L chlorine is not harmful to people, it does cause problems for fish if they are exposed to it over a long period of time.

Here in the scientific section, I'm going to ask you to cite some proof of this statement. The number 1.0 ppm is mentioned very specifically here, but all it does is "cause problems". What problems exactly? Please be very specific instead of using generalities. Thanks.

 

[rhostog]

Although 1.0 mg/L chlorine is not harmful to people, it does cause problems for fish if they are exposed to it over a long period of time.

Here in the scientific section, I'm going to ask you to cite some proof of this statement. The number 1.0 ppm is mentioned very specifically here, but all it does is "cause problems". What problems exactly? Please be very specific instead of using generalities. Thanks.

The figure of 1.0 mg/L (and accompanying text) posted above by fishyfeet is also quoted on:

[URL="http/www.h2ou.com/h2wtrqual.htm#Chlorine"]http/www.h2ou.com/h2wtrqual.htm#Chlorine[/URL]

which is an educational resource by a water analysis company called Hach. This resource is aimed at children so the information is simple and high level. The reference cited for the data is a US Environmental Protection Agency document from 1976.

I had a quick look for some more technical sources. I'm sure others could do better if you have some time to spend sifting through references.

A reference commonly cited on chlorine toxicity in fish was Noga, E.J. 1996. Fish Disease: Diagnosis and Treatment, Mosby-Yearbook, St. Louis, MO, 226-227, 367 pp. Couldn't see it available online, but didn't look for long so it's possible the full-text is out there somewhere.

According to the Merck Veterinary Manual on the subject of chlorine and fish, 'adverse effects seen at concentrations of 0.02 mg/L and deaths occurring at 0.04 mg/L'. Unfortunately the online manual doesn't cite a source reference for this data.

There is a paper at [URL="http/www.academicjournals.net/fulltext/ajava/2008/303-306.pdf"]http/www.academicjournals.net/fulltext/a...008/303-306.pdf [/URL]
describing the histopathological effects of (accidental) chlorine poisoning on rainbow trout, a relatively sensitive species. The residual Cl concentration in this incident was about 0.2 ppm. The fish had suffered severe damage to the gills and destruction of red blood cells as well as other organ damage.

Reading around the topic, it seems that fish vary significantly in their sensitivity to chlorine and other toxins, so not surprising there is so much anecdotal evidence of healthy fish in chlorinated water. A quick google search will show that there is quite a bit of scientific evidence that chlorine and chloramine at typical tapwater concentrations are harmful to many species of fish, and a bottle of pond dechlor works out at a few pence/cents per water change - the risk/benefit analysis is up to you.

 

[Bignose]

1 mg/L and 1 ppm is the same thing. I'll look at the sources later when I have more time.

 

[mike os]

both the above refer to prolonged exposure to relatively high levels of chlorine or give no "real" data....... only comment I thought was really relevant was

View attachment Doc1.doc

so what use is thiosulphate based dechlor?.....as most are?

 

[rhostog]

both the above refer to prolonged exposure to relatively high levels of chlorine or give no "real" data....... only comment I thought was really relevant was

View attachment 54231

so what use is thiosulphate based dechlor?.....as most are?

I agree that there is no real data in the paper quoted by fishyfeet, and while I'm used to treating Merck data with respect, it's open to question without seeing the source. However, the rainbow trout incident contains real data, and cites references to multiple sources.

The document you attach doesn't open properly on my computer, but seems to contain an extract from the Mahjoor & Loh paper, about the chlorine content after adding sodium thiosulphate. I understood that sentence to mean that the water authority had added sodium thiosulphate, but not enough to neutralise all the chlorine, so there was still 0.2ppm left. I don't think it is implying that sodium thiosulphate is not an effective chlorine neutraliser. Reading up on the chemistry, I haven't seen that disputed - provided you add the correct dosage. But you might be able to point me at some references that contradict this?

I'm not sure what you mean by 'relatively high levels' - my water authority declares an average level of 0.515 mg/L total chlorine at the customers' tap in our water supply. The fish in this paper were exposed to 0.2 mg/L (as Bignose points out, mg/L is equivalent to ppm for practical purposes in this context). The catfish in the cited paper by Mitz & Giesy died at total chlorine concentrations of 0.24-0.3 mg/L.

Edited for typo (thiosulphate).