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Carbon filter and chlorine in tap

1373 Views 7 Replies 5 Participants Last post by  BuckeyeFieldSupply

I wonder if carbon filter system is effective for reducing chorine in tap water? (not to be used in the tank!)
I'd be glad to hear it from you guys and not the sweet talk of a salesman.
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I am sure it would probably reduce it, but by how much would be my question.
You can reduce chlorine to a point that it can't be measured with consumer (hobbyist) test kits. It's easy with a carbon matrix (block) filter. When you fill the tank, you have to run the water through the filter. Some places sell in-line carbon filters. I use two carbon matrix filters inside a couple of RO canisters, run in series.

This only works for chlorine though, not chlorimine (did I spell that right?) The latter will leave a large ammonia residue, which will have to be removed. But chlorine - no problem - with the right filter.

Any carbon block filter sold at a place that sells RO stuff will work. The smaller the micron pore size, the more efficiently it will work. I use a 10 micron, followed by a 2 micron. But you can easily check your results with a test kit.
Thanks! really appreciate the info, right from hobyist mouth. It your fish aint dead yet from using such way, it surely does work well reducing excess chlorine. The sales is not giving me some crap info after all, even though I can see that it would be much more effective at slow rate of flow.

At least now I know of and easy way to deal with chorine in tap water (pretty sure they never put chloramine in tap). Usually chlorine is always trace around here, but sometimes the water company may mess up and the concentration may elevate without warning for a short while, and this may be dangerous when introduced into a tank at sudden rate.
Your situation may be different in Jakarta, but if you can contact your water company and ask about chlorimine, it would be a good idea. I gather that it is somehow cheaper than chlorine (could be wrong about that) and many water companies in the US that currently use chlorine have plans on the drawing boards to switch to chlorimine. So before I set my filters up, I got in touch with people in the know at my water company.

It seems like a small change, but it would mean a wonderful water change system suddenly changes into a water plus ammonia changing system - could destroy a tank quickly.

I wouldn't worry about slight elevations. If it doesn't bother people, I'll wager carbon blocks will still pull it out fine - as long as you are not pushing it through too quickly. Or if you are really worried, you can put multiple in series.

I communicated with someone (maybe here?) that said they used 3 in series. With my two I cannot measure any trace of chlorine. And I've given it to my family to taste, and they all find the difference in taste between the water going to my tank, and our tap water, to be dramatic. And all I do is push it through two carbon block filters.

Hey, my discus make whoopie in it. How bad can it be? Good luck!
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Thanks steve!

I'm very sure that they are using chlorine, and up to date I could still smell it in tap water. Most of the times the smell is so faint that I can go ahead and mix it in straight away without any preparation. No fish is lost this way.

I decided to try out just one carbon block as a start and see how it works. The system set is quite affordable here, costing at just $12 for one set of canister and a carbon cartridge. Refill cartridge costing at just $5.
This thread got me curious. Also since I will be setting up a 75g tank soon, I wanted to know about my local water.


Q: What is Chloramine?

A: Chloramine is formed when ammonia is added to water that contains free chlorine. Depending upon the pH and the amount of ammonia, ammonia reacts to form one of three chloramine compounds. NH2Cl, monochloramine, is the preferred compound and is the one Washington Aqueduct will produce.

Q: Is chloramine safe and are there any negative effects to the changeover?

A: Yes. Chloramine is safe. EPA accepts chloramine as a disinfectant and recognizes its ability to control THM formation. Chloraminated water is safe for bathing, drinking, cooking and all everyday uses. For the majority of the consumers there will be no negative effects as a result of the change. However, there are two groups of people who need to take special care with chloraminated water: kidney dialysis patients and fish owners.

Q: What about fish tank owners?

A: Fish tank owners, including hobbyists, restaurants and fish markets, who now treat for chlorines in the water, should assure that they have appropriate carbon filtration equipment or use water treatment products that neutralize chloramine. These products are readily available through pet and aquarium stores, as well as from companies that service commercial fish tanks

Q: Are Koi fish affected by chloramine like other fish?

A: Yes. Koi are just as susceptible to being harmed by chloramine as any other fish.

Q: Are salt water fish affected by chloramine?

A: Yes.

Q: Does letting water sit for a few days remove chloramine from tanks for pond water?

A: No. Unlike chlorine, which breaks up when water sits for a few days, chloramine may take weeks to disappear. If you choose not to use de-chloraminating chemical, install a granular activated carbon filter and allow sufficient contact time between the water and filter.

Also click here for what they recommend to remove chloramine.

For my interests, basically umm they say to... add Sodium thiosulfate but then ammonia is released.

So I am left with how to deal with that.

I will do more searching, I am sure it is adressed somewhere here, however if anyone who has more experience and knowledge point that out for me.. that would be great.

EDIT: and that answer is here!

Basically use Seachem Prime when filling your tank/dechloring to also remove/negate ammonia.
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When we configure RO or RODI systems to deal with tap water containing chloramines, we use a catalytic GAC stage in front of a vry high quality carbon block.

If you are not using RO or DI - just carbon filtration, expect that your post-carbon water will have ammonia in it.

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