Questions About Testing Your Tap Water

[Rhindon]

I couldn't find anything in my search, so I thought I'd post the question here.

I thought when someone asked me about my tap water readings that it's literally right after it's been poured from the tap. Then I thought someone else asked a member if they'd let their water "sit" about 24 hours, then I think someone else said it should be dechlorinated tap water. so I guess my question is exactly what is the proper procedure for the water from the tap before testing it?

Thanks in advance!

 

[Geoff-]

if you're testing tap water parameters then you don't need to dechlorinate, that's only for protecting your fish and bio filter.

the reason people let water sit is because tap water often has a lot of dissolved CO2 to reduce corrosion in the water pipes. CO2 forms carbonic acid which lowers pH slightly, so your pH may ultimately settle if you let the water gas off.

I don't think it matters unless your fish are especially sensitive. I routinely fill my tank with a hose under the water surface (to avoid disturbing the substrate) and it has loads of dissolved gas in it. The fish don't seem to mind!

 

[Rhindon]

Thank you for your reply. We are trying to determine the ammonia amount in my tap water. Would letting it sit and/or dechlorinating it affect the reading? Trying to find out how much (if any) ammonia I am putting in the newer tank during a water change.

 

[BigbruiserAl]

For the purpose of testing yes leave the water to sit 24hrs before testing geoff explained it pretty well, if your going to test you may as well do it right.

 

[Hermithall]

Thank you for your reply. We are trying to determine the ammonia amount in my tap water. Would letting it sit and/or dechlorinating it affect the reading? Trying to find out how much (if any) ammonia I am putting in the newer tank during a water change.

Hi, it depends on whether or not your tap water contains "chloramine" (different to chlorine). Chlorine has no bearing on ammonia readings, so you'll get the same ammonia reading whether you test your tap water straight away or after you dechlorinate or after you let it sit. Chlorine will evaporate from the water if you let it sit for 24+ hours.
Chloramine however is different, it will NOT evaporate from the water as chlorine does (hence becoming more popular with water companies). Chloramine is a chemical compound - it is actually chlorine and ammonia locked together. However, the ammonia would only show up on your test results AFTER you dechorinate, thus freeing up the ammonia into the water. Chloramine is bad news for fish-keepers really. So, to establish whether or not you have chloramine in your tap water, do the following experiment.

1. Test your untreated tap water for ammonia and note the reading.
2. Test some DECHLORINATED tap water for ammonia and note the reading.

If the second result is higher you have chloramines in your water. In this case, to deal with the unavoidable ammonia going into your tank during water changes, you could consider conditioning the new water with Prime, or any other product that "locks" ammonia (converts it to a harmless form - ammonium).
Maybe you could also contact your water company for a breakdown of your water parameters
Hope this helps

 

[Rhindon]

Ok, checked it last night after a couple of hours, but with dechlorinator, about 0.5 ammonia. However, that was not Prime, it was another product.

I purchased Prime the other day as well. I will check that sitting water again tonight, run the experiment you suggested, and re-run the experiment with Prime to see if the results are any different.

Thanks for all the advice everyone!

 

[Katch]

As a matter of interest, your local water board will have publically available reports on the quality of the water that they pump into your house. These are usually available online.

These test will be far more accurate that our home test kits will ever be.

 

[Rhindon]

As a matter of interest, your local water board will have publically available reports on the quality of the water that they pump into your house. These are usually available online.

These test will be far more accurate that our home test kits will ever be.

I don't see any ammonia on our report, here is the link: Water Quality Report

See anything I should be aware of and how to treat it?

 

[Katch]

Occaisionally high chloramines in your water but your dechlor will take care of that.

 

[Rhindon]

Can't figure out why I'm reading ammonia (0.5 or higher) and nothing mentioned about it in their report.

 

[Hermithall]

Note: Prime, or similar product that deals with ammonia, does not make it vanish but merely converts it to a safe form (ammonium) - so bear in mind it will still show on your test readings. You'll have peace of mind though, knowing it's in it's safe form and your beneficial filter bacteria will still consume ammonium in the same way as it does ammonia.

It's bad luck you have ammonia in your tap water - you'll confirm if your reading was from breaking the chloramine compound when you do your test with unchlorinated water (no ammonia present with unchlorinated will indicate chloramine).

Can't figure out why I'm reading ammonia (0.5 or higher) and nothing mentioned about it in their report.

You have chloramine in your water, as suspected. Chloramine is chlorine and ammonia bonded together. When you add dechlorinator to your water, you get rid of the chlorine but release the ammonia into the water.

Occaisionally high chloramines in your water but your dechlor will take care of that.

It would take care of the chlorine, but what about the ammonia which is then released into the water? Chloramine = chlorine+ammonia.

 

[Katch]

Occaisionally high chloramines in your water but your dechlor will take care of that.

It would take care of the chlorine, but what about the ammonia which is then released into the water? Chloramine = chlorine+ammonia.

Most turn it into ammonium as you mentioned earlier not ammonia.

 

[Rhindon]

And the ammonium will still read as ammonia in my tap water?

 

[Hermithall]

Occaisionally high chloramines in your water but your dechlor will take care of that.

It would take care of the chlorine, but what about the ammonia which is then released into the water? Chloramine = chlorine+ammonia.

Most turn it into ammonium as you mentioned earlier not ammonia.

Some do, some don't. Ones labeled as just 'dechlorinator' are often exactly that and only remove chlorine, I'm just wanting to be clear

And the ammonium will still read as ammonia in my tap water?

Yes.

 

[Rhindon]

I don't remember which dechlorinator I have, just that it's in a yellow bottle. I'm at work now or I would check. I will use the Prime for water changes in the new tank, and finish off that bottle in the healthy 37 gallon tank with water changes since the filter is established.

Will perform new experiments tonight and tomorrow and report back the results.

Thanks everyone!