Ammonia readings with copper

[mfinn]

Yesterday morning I noticed my seachem ammonia alert badge in my quarantine tank ( 29 gallon) was showing ammonia, which didn't surprise me too much. I have been feeding the 4 leopard wrasses 4-5 times a day ( very light feedings)
I'm using Coppersafe at about just below 2.0ppm
I tested with a old API ammonia test kit and it showed really high ammonia. But it's 10 years old and I don't trust it.

So I mixed up 15 gallons of water and added the appropriate amount of coppersafe and did the water change making sure no uneaten food was left over. Didn't really find much.

After the water change I replaced the ammonia badge ( after putting it in a different tank to reset it )
It went back to showing ammonia.
So I repeated the same steps late in the afternoon.
This morning I went and bought a new API ammonia test kit and it showed between 0.50 and 1.0 ppm.

So I did another 15 gallon water change.
But while I was waiting for the water to drain, I tested the new mixed saltwater ( with added copper) and it showed about 0.50ppm ammonia???????

So, does copper in saltwater give a false positive for ammonia?

 

[mfinn]

I tested the ro water and it was 0

 

[NanaReefer]

Sounds like the API is reading NO4 giving you a false positive. I've experienced this before.
I'm not familiar with the SeaChem badges.

 

[mfinn]

Then that must be the reason the seachem ammonia badge showed ammonia.

 

[Humblefish]

So, does copper in saltwater give a false positive for ammonia?

Yes, although Seachem's ammonia test kit claims to measure accurately even in the presence of copper. I know the alert badge still works in copper.

 

[mfinn]

The new test kit I bought this morning was a API ammonia test kit.
That one has to be giving me a false positive because I tested fresh mixed saltwater with copper added.

After 3 large water changes the seachem ammonia alert badge has returned to nearly normal. Still seems like it has a tiny tinge of color.

 

[melypr1985]

So, does copper in saltwater give a false positive for ammonia?

Yes. You will get false positives with the liquid test kits with the presence of copper. That's why we always recommend getting the alert badge. Make sure your viewing it in a white, clear light. I keep my living room dim and the badge would always appear slightly green until I used a white flash light to look at it and it was actually yellow the whole time.

 

[jd371]

Yeah, I'm getting a slight tint too with the badge, I'm using Coppersafe. The only reason I wasn't too concerned was because the filtration in the QT has been established now for over 6 months and the fish are fine and eating well.

 

[mfinn]

Yeah, I'm getting a slight tint too with the badge, I'm using Coppersafe. The only reason I wasn't too concerned was because the filtration in the QT has been established now for over 6 months and the fish are fine and eating well.

I too have a established sponge filter, but still had ammonia.
I've read that copper does put a dent in the bacteria population.
I guess maybe that and extra feedings could have been the cause for the ammonia alert badge to show ammonia.

 

[Humblefish]

I too have a established sponge filter, but still had ammonia.
I've read that copper does put a dent in the bacteria population.
I guess maybe that and extra feedings could have been the cause for the ammonia alert badge to show ammonia.

IME; it takes at least a solid month down in the sump for a sponge to be "well seeded" for QT use. Longer is always better. Or if you're going to use one of those bacteria in a bottle products to seed, let the bacteria "settle in" for a few days before dosing medication(s).

 

[mfinn]

I keep at least one sponge filter in the sump of my 233 year round .
This one might have been 6-7 months old.