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Long Shot - our waters contaminated

2207 Views 9 Replies 7 Participants Last post by  Donfish
as i live in Northamptonshire, UK, our water has unfortunatley been contaminated with cryptosporidium bacteria. i got in contact with our water board (Anglian Water) and they advised me not to use the tap water in my fish tanks, as this bacteria is dangerous to all living creatures, including aquatic life. i mentioned de chlorinator (aquasafe) and unfortuntley they didnt know!

so, im just wondering... will de-chlorinator actually work effectivly in getting rid of this bacteria?
or will i have to use a UV light to kill this bacteria off?

we are currently living off bottled water right now :lol:

anyway, thanks!
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I wouldn't think that it would since that's not what it's for. I would go with a UV sterilizer and boiling the water. I would also contact the water company again to see if boiling alone would be effective. That might save you some cash since you might not have to buying a UV sterilizer if it is.
A hard boil will kill off cryptosporidium but obviously does not remove the dead cells and potentially any toxins they may release, I would be hesitant to advise you to do that. I'm sure it would work but it would carry a small risk, if you boiled it and then filtered it using carbon chips/something similar you would then remove any by-product nasties but this is a lot of work for a WC - why not contact your local fish store and see if you can get a big barrel of RO which you can then buffer to the correct parameters, cheaper and easier then the other methods.

Dechlorinator will at most detoxify nitrite/nitrate and ammonia as well as binding heavy metals, but that is it, hydrogen sulfide (the main ingredient afaik) itself is pretty harmful to bacteria but only in large concentrated doses (ie you'd wipe everything out).

I'd look at getting a barrel of RO, if you only need to do a small change you could go posh and use bottled water but I'd be more inclined to go the RO and buffering route.
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You could chlorinate the water to kill the bacteria, then dechlorinate to remove the chlorine. It takes very little bleach to get a high enough concentration to kill the bacteria. Four or five parts per million should do it. Swimming pools are kept at 1 to 1.5ppm, as a comparison.
You could even sand filter < add H2O2 < dechlor.....

A few points:
Laboratory tests conducted by fish culturists in recent years have demonstrated that common household hydrogen peroxide can be used safely to provide oxygen for small fish.
The United States Food and Drug Administration (FDA) has classified hydrogen peroxide as a Low Regulatory Priority (LRP) drug for use in controlling fungus on fish and fish eggs.
Hydrogen peroxide is generally recognized as safe (GRAS) as an antimicrobial agent, an oxidizing agent and for other purposes by the US Food and Drug Administration.[13]

Hydrogen peroxide has been used as an antiseptic and anti-bacterial agent for many years due to its oxidizing effect
Just in case you were worried about using the stuff :)

(Good call BillD)....
thats very interesting information, blairo. Is there a website you know of where I can read more?
hmmmm, thats very interesting actually. im not too sure chlorine or hydrogen peroxide will work effectively in killing that bacteria. if it was that easy, i think our water would be good by now.
i have just had a letter through the post saying it will be another 3 weeks until the water is safe to drink etc.
i *think* that the water board is using huge amounts of UV light to kill this bacteria off, but i have no idea how to set this up.

i was thinking maybe filling up the guest rooms bath tub, and setting up an external and UV light filter, so i can then put this water in the tanks?
i was thinking maybe filling up the guest rooms bath tub, and setting up an external and UV light filter, so i can then put this water in the tanks?
Seems like it would work to me! Especially if that is how they are doing it for the city. (well basically)
H2O2 should kill cryptosporidium - it's the oxidizing properties which make it lethal to these types of bacteria. H2O2 is what is recommended for use in survival situations to purify water of cryptosporidium and a host of other nasties in instances where other means are simply not applicable. It is worth pointing out that crypto is notoriously resistant to chlorination (higher doses needed) so your scepticism is warranted!

H202 may kill the nasties, but it doesn't' actually filter out the by-products produced and so further filtration is pretty essential - hence why I recommended using sand - another survival technique is to use river bed sand to filter out the dead cells etc etc before and after treating with H202, if you really wanted to be safe you could finish with a quick boil. This (ie the whole process) removes the by-products resulting from the oxidization of the bacteria.

They say a hard boil can kill cryptosporidium but I'd be dubious of that - again even if effective simply boiling will not do anything to remove the then dead cells etc.


The water company will not be allowed to add H202 in the sorts of quantities required to deal with such a problem because - a. it's not as cost effective, b. there are set regulations for acceptable quantities of chemicals/organics in drinking water. They will use UV because it is far cheaper for them as this process deals with the by-products - meaning they don't have to then filter all the water afterwards.

As you read above, using H202 with UV is the equivalent of nuking the little blighters.....

If you can afford it, definitely go with the UV sterilizer.
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Cryptosporidium has a spore phase (oocyst) and in this state it can survive for lengthy periods outside a host. It can also resist many common disinfectants, notably chlorine based disinfectants. As a result of this resistance, water purification to eliminate Cryptosporidium generally relies upon coagulation followed by filtration or boiling. Recently, it has been discovered that Cryptosporidium is sensitive to ultraviolet light and ozonation, and water treatments based on these sterilization methods are being developed.

The cyst phase is why it is so dangerous.

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