Possible causes for API Ammonia false positives

[ThePlummer]

Interference with ammonium determination by the indophenol-type reaction of salicylate and dichloroisocyanurate - Analytical and Bioanalytical Chemistry

Two widely accepted indophenol-type reactions with ammonium, which use phenol/hypochlorite and salicylate/dichloroisocyanurate as reagents, were compared for possible interferences with other naturally occurring nitrogen-containing compounds. Unlike the first method, the second showed strong...

link.springer.com

Interesting.... If I'm interpreting this correctly, and from memory I believe the waste away bacteria is basically biological bacteria, that would contain amino acids. So, I'm going to make a hypothesis that the testing chemicals are breaking down the bacteria, and it's showing a false positive, from the free floating bacteria in the water column.

If this is correct, this could be a good way to measure the amount of bacteria in the water column for dosing purposes. Or,... I could just be missing the point.

 

[Dan_P]

For the last three weeks or so, I've been really worried about the ammonia levels in my display tank, as they have been steadily creeping up and now they are up to 5.0ppm, but the water is clear and the fish are healthy. So, obviously I have a API test kit that is giving a false positive, but only in this tank. It tests fine in the three other tanks that I have set up and I've checked with another lot batch test kit and get the same results.

My question is two fold: Is it possible that vodka dosing can cause a false positive, Dr. Tim's Waste Away, or a combination of both being used. I've been fighting a crazy high nitrate problem (off the charts) and started vodka dosing. I've never done that before but have been told that once you start, you shouldn't stop. During this time, LFS store sold me waste away. I must say, over the next month.... YUP, nitrates are now down to 5-10 range and staying consistent.

Consequently, now I have a major breakout of either red cyano or dinos. Nothing has worked getting rid of those. If I scrub them off the rocks, by the next day, this is everywhere, so that doesn't work.

I've stopped vodka dosing all together and have suspended Dr. Tim's for now, hoping that the ammonia levels would drop... It's been nearly a week and nope, still 5.0 on the ammonia.

Any thoughts?

You have an anaytical chemistry mystery and possible nutrient issues with your system. I agree with @taricha that you should sort things out before adding anything to this system.

Purchase a Seachem ammonia test kit. The Seachem method uses a colorimetric film that is highly selective for ammonia (NH3) and rivals Seneye for detection level. This kit will inform you whether the thing causing the deep color in the API test is ammonia or not. @taricha can answer your questions about this kit. I learned much from his studies.

As for WasteAway or carbon dosing causing the high API readings, they are both unlikely candidates.

 

[Malcontent]

Interesting.... If I'm interpreting this correctly, and from memory I believe the waste away bacteria is basically biological bacteria, that would contain amino acids. So, I'm going to make a hypothesis that the testing chemicals are breaking down the bacteria, and it's showing a false positive, from the free floating bacteria in the water column.

It's just that the salicylate method is rather prone to interference. In freshwater forums, I see people with off-the-scale ammonia readings fairly regularly but the fish are fine. They are often using Ammo-lock which is said to be amine-based.

One of these days I'm going to fill a 10 gal tank with new water and dose enough ammonium chloride to get to, say, 1 ppm. Then test ammonia. Then add Ammo-lock and test again. If it goes haywire and reads 8+ ppm then I know it's the Ammo-lock.

 

[taricha]

When i've looked, Waste Away showed no ammonia. Also no ammonia from a cloudy water bacterial bloom caused by carbon dosing. Not at first anyway. Creating a bacterial bloom in a bottle, after several days of bloom, the ammonia reading from API kit climbed and stuck around ~1ppm. Was that ammonia from the bacteria dying? Or was it other nitrogen compounds released by the bacteria? I don't know.

 

[ThePlummer]

When i've looked, Waste Away showed no ammonia. Also no ammonia from a cloudy water bacterial bloom caused by carbon dosing. Not at first anyway. Creating a bacterial bloom in a bottle, after several days of bloom, the ammonia reading from API kit climbed and stuck around ~1ppm. Was that ammonia from the bacteria dying? Or was it other nitrogen compounds released by the bacteria? I don't know.

Ohh my, I surely didn't expect you to do an experiment on my behalf, but I truly thank you nonetheless.

At this point, I'm not actually sure if I have dinos or cyano. I've raised the temp in the display tank to 82, and low and behold, the bloom has increased dramatically.... I suppose that's a definitive answer in and of itself as being cyano.

There's a lot more I can add to this story. I've recently purchased a used Innovative Marine 20 gal. peninsula that came with a Fluval Aquasky light (not particularly designed for reef), but since this is a FOWLER anyway, I opted to move the reef lights, (Orbit Marine Pro) back to the 14 peninsula, and move the Oceanrevive light to the new 20 peninsula. It just fits the larger tank better. I've put some coral rock that I'd been seasoning in a tub, in the 20 gal., ghost fed the tank, and waited for a couple of days to see if I had an ammonia spike, or if the cycle was complete on the corals. Ammonia was barely detectable, so I put the two clownfish that I had in another 6 gallon tank (that is also suffering greatly with the same red slime.

I've since put a black trash bag over the 6 gallon last night, to see if in a few days, this knocks down the stuff.

I've got Chemiclean on it's way, should arrive tomorrow.... We'll see if that helps in the display.

I'll continue to monitor my ammonia, nitrite, and nitrate levels moving forward. I'd like to figure this out, for when I get the 120 rolling, I want to avoid this same issue, or know what to do should it arise.

I'll attach a pic to this thread of the 20 to show how much rock is in there.

 

[ThePlummer]

This was a pretty good deal. $275 for tank, stand, Fluval light, and two mighty jet pumps (only one controller sadly).

 

[taricha]

Ohh my, I surely didn't expect you to do an experiment on my behalf, but I truly thank you nonetheless.

Heh. I'm just doing weird stuff like this most of the time. Those were a few months ago, they just happened to be relevant.

 

[ThePlummer]

Heh. I'm just doing weird stuff like this most of the time. Those were a few months ago, they just happened to be relevant.

The plot thickens... Put 1/2 dose of waste away in Sunday, checked Ammonia today.... Down to .25 The only thing I'm not doing is the Vodka dosing. I wonder if together they are giving the false positive.

 

[Randy Holmes-Farley Verified Community Expert]

The plot thickens... Put 1/2 dose of waste away in Sunday, checked Ammonia today.... Down to .25 The only thing I'm not doing is the Vodka dosing. I wonder if together they are giving the false positive.

Vodka would not contribute to test result inaccuracy.

 

[melissa1076]

For the last three weeks or so, I've been really worried about the ammonia levels in my display tank, as they have been steadily creeping up and now they are up to 5.0ppm, but the water is clear and the fish are healthy. So, obviously I have a API test kit that is giving a false positive, but only in this tank. It tests fine in the three other tanks that I have set up and I've checked with another lot batch test kit and get the same results.

My question is two fold: Is it possible that vodka dosing can cause a false positive, Dr. Tim's Waste Away, or a combination of both being used. I've been fighting a crazy high nitrate problem (off the charts) and started vodka dosing. I've never done that before but have been told that once you start, you shouldn't stop. During this time, LFS store sold me waste away. I must say, over the next month.... YUP, nitrates are now down to 5-10 range and staying consistent.

Consequently, now I have a major breakout of either red cyano or dinos. Nothing has worked getting rid of those. If I scrub them off the rocks, by the next day, this is everywhere, so that doesn't work.

I've stopped vodka dosing all together and have suspended Dr. Tim's for now, hoping that the ammonia levels would drop... It's been nearly a week and nope, still 5.0 on the ammonia.

Any thoughts?

I know this is an old thread, but still thought it might help someone else out.

We were having the false positive and figured out today that if you use PRISTINE in your aquarium (ours is salt water) it WILL show positive for .5 - 1 ammonia. We used our tap water as a test, one without Pristine and just water and one with pristine, sure enough, the one treated with pristine went green fast. The tap stayed yellow with zero detection. Hope this helps someone else out!

 

[Randy Holmes-Farley Verified Community Expert]

I know this is an old thread, but still thought it might help someone else out.

We were having the false positive and figured out today that if you use PRISTINE in your aquarium (ours is salt water) it WILL show positive for .5 - 1 ammonia. We used our tap water as a test, one without Pristine and just water and one with pristine, sure enough, the one treated with pristine went green fast. The tap stayed yellow with zero detection. Hope this helps someone else out!

Welcome to Reef2Reef!

Do you know if your tap water supply contains chloramine? If so, it can react with organics in the Pristine to produce ammonia, which would show on the ammonia test.

 

[helovsu]

For the last three weeks or so, I've been really worried about the ammonia levels in my display tank, as they have been steadily creeping up and now they are up to 5.0ppm, but the water is clear and the fish are healthy. So, obviously I have a API test kit that is giving a false positive, but only in this tank. It tests fine in the three other tanks that I have set up and I've checked with another lot batch test kit and get the same results.

My question is two fold: Is it possible that vodka dosing can cause a false positive, Dr. Tim's Waste Away, or a combination of both being used. I've been fighting a crazy high nitrate problem (off the charts) and started vodka dosing. I've never done that before but have been told that once you start, you shouldn't stop. During this time, LFS store sold me waste away. I must say, over the next month.... YUP, nitrates are now down to 5-10 range and staying consistent.

Consequently, now I have a major breakout of either red cyano or dinos. Nothing has worked getting rid of those. If I scrub them off the rocks, by the next day, this is everywhere, so that doesn't work.

I've stopped vodka dosing all together and have suspended Dr. Tim's for now, hoping that the ammonia levels would drop... It's been nearly a week and nope, still 5.0 on the ammonia.

Any thoughts?

AMMO LOCK solved the problem in my tank with my false readings if they were false. I followed the directions, change the water, a couple of times, and used ammo lock and now the reading is completely gone. So happy! Started out at 2.0, and now the reading is in the yellow!

 

[taricha]

AMMO LOCK solved the problem in my tank with my false readings if they were false. I followed the directions, change the water, a couple of times, and used ammo lock and now the reading is completely gone. So happy! Started out at 2.0, and now the reading is in the yellow!

To be clear, ammo-lock contains dechlorinator/reducer compounds and thus it interferes with the Total Ammonia test.

So even if there were actual ammonia still present it will make the ammonia test read reduced or zero ammonia.
If you want a more reliable marker for ammonia (while adding a dechlorinator/reducer) an ammonia alert badge would be much harder to interfere with than the total ammonia test.

I love a total ammonia test but I'm increasing my appreciation for the wide number of compounds that can interfere with the test chemicals/conditions (hypochlorite, chloramine, high pH)