Chloramine = low level ammonia readings?

[cherryshrimp]

I never get a true yellow 0 Ammonia reading (API liquid kit) out of any of my 3 tanks. It reads about .1-.2, always a bit more yellow than .25 but definitely still a bit of green. Aside from a tank where I experienced an outbreak of fin rot with nipped guppies, the fish and shrimp are all doing well and spawning/breeding. Could this low level ammonia in all tanks reading be caused by chloramine in the tap water that is broken down into Ammonium? And is this a cause for concern? Thanks for any advice!!

 

[Retired Viking]

Yes, when you use conditioner on chloramine it unbinds the chlorine from the ammonia they use to bind it. The ammoia is a different type and is used to help keep the chlorine from dissipating too fast like regular chlorine does.

 

[Essjay]

The ammonia formed when chloramine is split is the same ammonia as made by fish. Many water conditioners bind it to a less toxic form, but this can still be used by plants and bacteria. In theory, this ammonia is removed by plants/bacteria before it can revert back to the toxic form.

Some people never see the zero colour for ammonia. There are various theories from the type of light the colour is read under making the water look greener than it really is, to the way different eyes work.

 

[cherryshrimp]

The ammonia formed when chloramine is split is the same ammonia as made by fish. Many water conditioners bind it to a less toxic form, but this can still be used by plants and bacteria. In theory, this ammonia is removed by plants/bacteria before it can revert back to the toxic form.

Some people never see the zero colour for ammonia. There are various theories from the type of light the colour is read under making the water look greener than it really is, to the way different eyes work.

I can see the true yellow if I test tap water, before dechlorinating. I will dechlorinate some tap water, let it sit out for 24 hours then test it again! I just want to make sure there isn't something going on in all the tanks

 

[Essjay]

When the water supply has chloramine, it is usual to see an ammonia reading in tap water as the test picks up the ammonia half a chloramine.

I would do 4 tests - plain tap water (again), tap water half an hour after dechlorinator has been added (to make sure that every chloramine has been split), dechlorinated tap water that has sat out and untreated tap water that has sat out. That way you can compare untreated tap water and dechlorinated tap water both freshly run, and samples that have sat out.

That will show if it's in the tap water or coming from something in the tank.

 

[cherryshrimp]

When the water supply has chloramine, it is usual to see an ammonia reading in tap water as the test picks up the ammonia half a chloramine.

I would do 4 tests - plain tap water (again), tap water half an hour after dechlorinator has been added (to make sure that every chloramine has been split), dechlorinated tap water that has sat out and untreated tap water that has sat out. That way you can compare untreated tap water and dechlorinated tap water both freshly run, and samples that have sat out.

That will show if it's in the tap water or coming from something in the tank.

That sounds even better! How long would you suggest I leave it to sit before testing?

 

[Essjay]

I would:
Run some water into a small container and test ammonia straight away. Leave it stand and test again 36 to 48 hours later.
Run some more water into another container and add dechlorinator at the dose rate you use in your tank. Stir it vigorously for 5 minutes or leave it to stand for 30 minutes (this is to allow the dechlorinator to mix in thoroughly) then test it. Leave it to stand and test again after 36 to 48 hours (the two tests on water that has stood should be the after the same length of time). The ammonia detoxification effect of dechlorinators wears off after about 24 hours so it should have completely gone after 36 to 48 hours.



The test on plain tap water as soon as it's been run should pick up the ammonia half of chloramine.
The test on dechlorinated water as soon as it's been thoroughly mixed in will show if the test picks up the ammonia which used to be in the chloramine in its detoxified state.
The test on dechlorinated water after it has stood for over 24 hours will show if the ammonia reading changes when the detoxification has worn off.
The test on plain water after it has stood will show if any change with dechlorinated water is due to the dechlorinator or just being allowed to stand.