Your Guide to Ammonia Toxicity

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As we seem to be doing a lot recently...I agree, lol. That said, I'd personally prefer that newbies run around telling other newbies that .25 is the safe threshold, as opposed to "2.0 is safe as long as your pH is 7.4 and their temperature is at 68 degrees". As the information you provided shows, small fractions of differences can result in dramatically different consequences (not even mentioning the lack of a quality test kit or using inaccurate strips which don't provide reliable and detailed results). With something as potentially detrimental as ammonia poisoning...someone armed with only partial information without knowledge or the ability to explain it can set a dangerous precedent. As you said, when people "parrot" :) the information they've heard...it often turns into a game of telephone where the only part of the information that sticks with the novice is that 2.0 is okay...leaving out the entire conversation of free ammonia vs. ammonium.

I agree that making people believe that the world is on fire without adequate explanation is somewhat equally irresponsible in it's own way. I think that I was personally guilty myself of probably scaring the heck out of a newbie or two when I was newer to the site...and have since made a conscious effort to avoid any type of fear based guidance unless it is appropriate (which I'm sure you've seen occasionally is).

The heart of this matter, IMO, again comes down to the level of experience of the hobbyist as well as commitment and willing to lean the sciences behind what it takes to maintain a healthy aquarium. Ideally, I wish there were 3 separate guides we could link to newbies based on their understanding and, to put it bluntly...their mental capacity to understand them.

First, the younger kid who won a goldfish at the fair and has it in a bowl, or someone who without research went out and bought a 10 gallon tank and stocked it to capacity immediately because they "cycled" it for a week (by which I mean running it empty at the advice of the chain stores), and assumed it was clear sailing. Then they are on the site asking why their fish are dying and gasping at the surface. In that case...they're instantly getting linked HN1's article linked by me (which is the source of why I follow the .25 guideline). I think you have to agree that article is based on this demographic judging by the title alone.

Second, I believe there are hobbyists who have gained the basic knowledge of what the nitrogen cycle entails, and it is our duty as more experienced members to link them to the proper articles so they have the opportunity to fully inform themselves of the science and reasoning behind our initial advice and what the consequences are if not followed. That is the key to becoming a successful fish keeper IMO, both being informed of the information out there, as well as the willingness or capacity to understand and learn about it. I believe this particular write up of yours belongs in this category.

Third, there are people like us who are borderline OCD and feel it is our duty to try and lean all the info we can about the different aspects of fish-keeping. To me as well as tons of others...we get excited when we see graphs and scientific data that relate to these aspects because not only does it help us personally to become better care takers to our own fish...but it gives us the ability to share the correct info with others.

Just to digress for a moment, jcolon and I had an interesting conversation unrelated to this a few days ago. He had mentioned that there are speed limits on every road. Now, I have law enforcement in my family as well as limited experience myself and he makes a fantastic point. Speed limits are posted on every road...and they are there as a safeguard. To use it as a metaphor...a skilled, experienced driver with a high end capable car may be perfectly safe and acceptable to go down I-95 at 100mph as long as they understand road conditions, reaction time, weather related variables, etc... However, for every capable driver, there are 100 people driving irresponsibly down the road on cell phones in cars with bald tires and bad breaks with only limited knowledge of what it takes to perform at these levels that are teetering on the edge of borderline dangerous situations. So, instead of posting graphs about traffic patterns and inclement weather...they post a set speed limit. It doesn't mean it is the whole story...but it is a necessary aspect that has to be taken into account when the states make the signs and hang them on the roadway. Not the same thing...but I think you have to agree there are similarities between the two.

To sum up...I will continue to link this to any and all members that I believe can benefit from it...but for the kid with the Pleco in a 10 gallon tank...he's getting HN1's guide for now ;-)

Thanks for writing it up though, I really do appreciate and respect it...and it is an invaluable tool to countless fish keeping enthusiasts in the world.
 
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I wrote out a really long response to this, but I since deleted it in an effort to keep it simple.

This guide was never intended to be comparable to the newbie guides, so I don't expect it to be. I do hope that those that can use a good test kit can make use of it if deemed necessary.
 
Great article! This should be quite useful for those of us who want to know more about how our aquariums work. I think it would be a good idea to post the equillibrium equation for ammonia and ammonium as well. I can't remember off the top of my head, but I can scrounge it up later if you want.

Also, while we're on the topic of the .25ppm ammonia "threshold", what makes it different from your .05mg/L and 2.0mg/L? My point being, the .25ppm is an approximation, as is the 2.0mg/L limit for fish death. Depending on the fish's biological processes and sensetivity, the 2.0 number could be very different for individual species. That threshold is a generalization, as is .25ppm. So IMO, .25ppm isn't such a bad number to throw around, as we can only ever approximate.

Oh, and I agree that daily PWCs aren't necessary during fishless cycling, however, they ought not to affect the cycling process as long as there is a supply of ammonia in the water. Once the bacteria are seeded on the filter media, they will continue to reproduce there, so changes to the water column won't affect them as long as their food supply is uninterrupted. You're waiting for bacteria to multiply in the filter media during a cycle, not in the water column.

Anyways, great writeup! This should totally get stickied or put in with the list of beginner articles!

--Adeeb
 
Great article! This should be quite useful for those of us who want to know more about how our aquariums work. I think it would be a good idea to post the equillibrium equation for ammonia and ammonium as well. I can't remember off the top of my head, but I can scrounge it up later if you want.

Also, while we're on the topic of the .25ppm ammonia "threshold", what makes it different from your .05mg/L and 2.0mg/L? My point being, the .25ppm is an approximation, as is the 2.0mg/L limit for fish death. Depending on the fish's biological processes and sensetivity, the 2.0 number could be very different for individual species. That threshold is a generalization, as is .25ppm. So IMO, .25ppm isn't such a bad number to throw around, as we can only ever approximate.


Anyways, great writeup! This should totally get stickied or put in with the list of beginner articles!

--Adeeb

Thanks everyone for the kind words.

The 'threshold' # that I am using is based primarily on the UFAS article on the subject. There is definitely some variance in how different species react, but I think it's a good general guideline.

.25 is a good target #, but sometimes just not possible for those with chloramines in their tap water, no matter how much water they change, if they are getting 1.0 out of the tap, for example, it'll never reach that .25 target. And to make matters worse, I've seen people go to the effort of getting bottled water or a ro/di filter just to get down to that .25 target, which is just a big waste of money IMO.

They do it because they think that "X" amount of ammonia in their tap is going to kill their fish, since they can't get it down to the .25 that everyone recommends.

Oh, and I agree that daily PWCs aren't necessary during fishless cycling, however, they ought not to affect the cycling process as long as there is a supply of ammonia in the water. Once the bacteria are seeded on the filter media, they will continue to reproduce there, so changes to the water column won't affect them as long as their food supply is uninterrupted. You're waiting for bacteria to multiply in the filter media during a cycle, not in the water column.
I understand how the bacteria colonization process works, but unfortunately everyone tends to overlook some major points in the process. Biofilm. Granted, the majority of nitrifiers are going to be found in the area with the most water flow, where their food source and oxygen is abundant. However, there is still a good bit of nitrifying bacteria in the biofilm along the tank walls and even in the substrate.

That said, doing water changes tends to dislodge/dry out the biofilm and disrupt things momentarily till everything gets stabilized again.

Nitrifiers don't free float, but they do use water as their medium, and they have to get around to the places that they colonize somehow. I've read that some species are motile. Doing big water changes can often give a big change to the parameters in the tank pretty quickly. This is better avoided by using an aging tank for fresh water, but most don't go to the trouble. Water straight out of the tap is often low in o2 or possibly high in co2, so you can imagine how radically it would have things swinging around till it stabilizes. Anyone that has noticed their fish gasping after a WC can attest to that.


Is this going to be detrimental to the beneficial bacteria colony? Likely not, but the main drive to avoid doing multiple PWCs is just the fact that it's often unnecessary to do so, and shouldn't be solely motivated by a partially true notion that the fish are going to die if you don't.


To sum things up, I am ok with daily pwc's if they are deemed necessary, but multiple daily pwc's I think are just a bit much. Maybe as an initial move to knock out an extreme toxin level, but not as a routine for fish-in cycling. If the ammonia level is rising that fast in the tank, then there are much bigger issues that need to be dealt with, like overstocking or overfeeding.

(a new look at fish-in cycling 'guide' in the works maybe?)
 
interesting footnote-
Present ammonia criteria for aquatic systems are based on toxicity tests carried out on, starved, resting, non-stressed fish. This is doubly inappropriate. During exhaustive exercise and stress, fish increase ammonia production and are more sensitive to external ammonia. Present criteria do not protect swimming fish. Fish have strategies to protect them from the ammonia pulse following feeding, and this also protects them from increases in external ammonia, as a result starved fish are more sensitive to external ammonia than fed fish.

-exerpt from study by National Institute of Health

 
Your charts are simply excellent. Any flak received makes it all too apparent that people want simplicity in this hobby over scientific understanding. Variation exists at every level, and this is an important one to consider. With chemical processes, there are tons of variants that can cause different "outcomes", if you will. Each system is different, yet when drawn into accordance with pH/temperature (two very important metabolic factors), you have a more 'uniform' guideline. Ultimately, these measurements are very useful in determining course of action if one does encounter such ppm readings of ammonia. One thing that I recommend adding are your unit of measure for the cells in the chart, at least via use of a key. Without your context, those numbers (ie: .0023) mean nothing...mg/L, uM,mM?

Your mention of biofilms is also noteworthy...people forget that bacteria in water exhibit adhesive/cohesive properties.

Also, are we talking immediate effects here (<1 week), or long term exposure (>1 week)? I think it's safe to infer that leaving your fish in a constantly toxic environment will have some strain on physiological processes regardless of deemed safe levels and the immediate threat that the ammonia imposes. Fish species needs to be taken into consideration as well. EVEN SO, this is a great compilation of data.

THUMBS UP!

(Edited several times after more reviewing)
 
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Thanks Nick, it really means a lot and is appreciated. tulip linked me to another good reference source so I'm going to be updating the charts shortly, and I'll definitely add a legend that indicates that all #'s are in mg/l (ppm).
 
free ammonia threshold of 0.0025 ppm?

It's mentioned in the first post that the threshold for free ammonia (NH3) is 0.0025... so shouldn't the yellow on the charts begin at 0.25ppm, 82F, pH 7.2?

Right now I think yellow begins at 0.025 ppm free ammonia on the charts..

Maybe the threshold is actually supposed to read 0.025 ppm? Please fix whichever one is incorrect! Thank you for the information though, it is very useful!
 
Yeah, this is an awesome write-up, but it seems that: The threshold level for Free Ammonia (NH3) .0025ppm
should have been .025?
It a great resource though! I have book marked it for future reference. I honestly did not know these things. Thanks. :)
 
absolutangel04 said:
Yeah, this is an awesome write-up, but it seems that: The threshold level for Free Ammonia (NH3) .0025ppm
should have been .025?
It a great resource though! I have book marked it for future reference. I honestly did not know these things. Thanks. :)

I believe it is correct, the .0025ppm is the threshold level for NH3, the API test only reads to .25ppm, so, that is why many people use .25ppm as the point at which you have a problem. In reality, any ammonia is bad!
 
The API test kit reads total ammonia, both NH3 and NH4+. The numbers in the tables here are concerning NH3 ONLY. As it is the toxic form. If the threshold is indeed 0.0025, the tables should be fixed! If it is 0.0025, there is supposed to be a lot more yellow
 
But the point of the chart is to look at how much of the TAN is actually free ammonia. The first chart is for the .25 reading the test kit gives you so you can determine how much of that .25ppm TAN is actually free ammonia ect. The post says the .0025ppm is the threshold, bit the individual charts are yellow over the free ammonia that is above .025ppm.
Unless there is a conversion I am missing somewhere. In that case, just let me know. :)
 
absolutangel04 said:
But the point of the chart is to look at how much of the TAN is actually free ammonia. The first chart is for the .25 reading the test kit gives you so you can determine how much of that .25ppm TAN is actually free ammonia ect. The post says the .0025ppm is the threshold, bit the individual charts are yellow over the free ammonia that is above .025ppm.
Unless there is a conversion I am missing somewhere. In that case, just let me know. :)

I'm not sure now! It's late, beer has been consumed and my head hurts :) every time I read it I get confused again!
 
absolutangel04 said:
Yeah, this is an awesome write-up, but it seems that: The threshold level for Free Ammonia (NH3) .0025ppm
should have been .025?
It a great resource though! I have book marked it for future reference. I honestly did not know these things. Thanks. :)

Having read it again, that seems more likely! .025 threshold.
 
Just wanted to add... I'm a newbie and understood this perfectly, and it's been massively helpful to my understanding while doing a fish-in cycle following poor advice from the petshop and Nutrafin claims! I like the science bit... Thanks v much :)
 
Just wanted to add... I'm a newbie and understood this perfectly, and it's been massively helpful to my understanding while doing a fish-in cycle following poor advice from the petshop and Nutrafin claims! I like the science bit... Thanks v much :)

I was in your shoes a few months ago. This info was also very helpful to me, and I didn't lose one fish. You really do have more leeway than others might have you think, and I believe that the frequent PWC's at .25 free ammonia slowed my cycle for some time....I never could get past the Nitrite stage and I think it was because I kept changing water to control ammonia, removing all Nitrites and making it impossible to develop that bacteria.
You're doing great!!! Good luck (y)
 
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