# Do plants use ammonia?



## boringname

Plants mostly absorb ammonium, not ammonia. But there is always some ammonium mixed in with the ammonia, the ratio depends on ph(lower ph means more ammonium). I think plants mostly absorb nitrates through their roots and ammonium through their leaves. I think what the fish pee out is ammonium and it only becomes ammonia when it reacts with the water. So it enters the tank as ammonium. If it was ammonia while still in the fish's system it would prolly harm them.

I think the reason plants absorb ammonium better is because its positively charged and plants absorb positively charged molecules better than neutral or negatively charged molecules.


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## Captivate05

Technically fish don't "pee out" ammonia/ammonium. When the urea in fish waste starts breaking down, it forms ammonia/ammonium.


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## Carson Albright

ok, well it's a snow day here in arkansas, so i've been doing a bit of research over this and thought I would clarify my question. I've found a few threads answering some portion of my questions, which is plants do use NH4(ammonium) 
http://www.plantedtank.net/forums/g.../32733-do-plants-really-use-ammonia-myth.html 
but what I'm confused about is whether they use ammonia(NH3), I'm actually having a pretty hard time distinguishing the difference between the two chemicals. From the reading I can find ammonia and ammonium are basically the same thing, but at a ph of 6.8 or lower its ammonium, and higher its the more deadly ammonia. Which is where I get stuck in my question of whether plants use it or not. Most scientific articles I've found refer to ammonia as NH4, but NH4 is ammonium. I might just be reading these wrong, but I've gone through a few articles in my college online library and they seem to use ammonia and ammonium interchangibly when refering to their uptake in plants.


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## Gatekeeper

Explanation on wiki I think is pretty good on the difference between the two.

http://en.wikipedia.org/wiki/Ammonium. Ammonia is NH3, Ammonium is NH4+



> The degree to which ammonia forms the ammonium ion depends on the pH of the solution. If the pH is low, the equilibrium shifts to the right: more ammonia molecules are converted into ammonium ions. If the pH is high (the concentration of hydronium ions is low), the equilibrium shifts to the left: the hydroxide ion abstracts a proton from the ammonium ion, generating ammonia.


Keep in mind, plants consume the nitrogen of the compound not the hydrogen. I don't know the chemistry for the byproduct. 

This falls into the basic regime of the Macro Nutrients, N P K, N being the nitrogen.

This is also why plants can assist with that terible phase of cycling a tank during those usual nasty ammonia spikes.


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## Carson Albright

So plants are able to take the N from the NH3? Another point brought up in our argument was that ammonia is toxic to plants. This was news to me, but before I started researching into this so was the distinction between ammonia/ammonium. If I am correct in assuming that plants can take the N from NH3 does that mean ammonia(NH3) is not toxic to plants?


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## legomaniac89

Just for clarification, this



> The degree to which ammonia forms the ammonium ion depends on the pH of the solution. If the pH is low, the equilibrium shifts to the right: more ammonia molecules are converted into ammonium ions. If the pH is high (the concentration of hydronium ions is low), the equilibrium shifts to the left: the hydroxide ion abstracts a proton from the ammonium ion, generating ammonia.


is because as pH drops, there is more free hydrogen (H+) in the water, thus the ammonia (NH3) picks up an extra H+ ion to form ammonium (NH4+). Conversely, as the pH rises to the alkaline area, the free H+ bonds with an oxygen atom to become hydroxyl molecules (OH-). This means the extra H+ in ammonium gets pulled away by the oxygen atom, which forms OH- and NH3.

if pH<7, NH3 + H+ = NH4+
if pH>7, NH4+ = NH3 + OH

According to Diana Walstad, there is no definitive evidence that plants take up NH3 directly. Rather, since NH3 has no charge, it can diffuse right through the plant cells while NH4+ cannot. But once the NH3 gets into the plant cells, it usually finds a free H+ atom and becomes NH4+ that the plant can then use and store.


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## Gatekeeper

I didn't know that Lego! I learned something today. The chemistry and biology of this is just not my thing.


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## legomaniac89

Carson Albright said:


> So plants are able to take the N from the NH3? Another point brought up in our argument was that ammonia is toxic to plants. This was news to me, but before I started researching into this so was the distinction between ammonia/ammonium. If I am correct in assuming that plants can take the N from NH3 does that mean ammonia(NH3) is not toxic to plants?


If you really want to get scientific about it, yes, eventually the NH4+ molecule gets broken down into its single atomic components for use by the plants. The only reason that plants take up NH4+ or NH3 rather than just N2 by itself is because they are much more readily available to plants than atomic nitrogen.

And yes, NH3 can actually be toxic to plants at high levels. At low levels, it is taken up as normal, but it can inhibit growth or completely kill plants at high levels, but these levels are almost impossible to reach in normal aquariums. The fish would die and you'd notice a terrible smell from the water long before you noticed any problems with the plants. 

Technically, anything can be toxic at high enough levels. Even oxygen can be a poisonous gas if the concentrations are too high.


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## Carson Albright

Ok, so in other words plants cannot use NH3 for purposes of helping through cycling, which is what interests me. However once diffused in a plant cell can be converted to NH4, and then used? So either way if you have plants in an uncycled tank, is it safe to assume that NH3 levels will be lowered just through the use of plants, or is that an unsafe assumption?


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## legomaniac89

Carson Albright said:


> Ok, so in other words plants cannot use NH3 for purposes of helping through cycling, which is what interests me. However once diffused in a plant cell can be converted to NH4, and then used? So either way if you have plants in an uncycled tank, is it safe to assume that NH3 levels will be lowered just through the use of plants, or is that an unsafe assumption?


Most likely, the _Nitrosomonas_ bacteria that convert NH3 into NO2- will get to the NH3 before the plants do, but they can help speed up the process.


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## boringname

Captivate05 said:


> Technically fish don't "pee out" ammonia/ammonium. When the urea in fish waste starts breaking down, it forms ammonia/ammonium.



http://www.nature.com/nature/journal/v337/n6203/abs/337165a0.html

"Ammonia is toxic to all vertebrates. It can be converted to the less toxic urea, but this is a metabolically expensive process1 found only in terrestrial vertebrates that cannot readily excrete ammonia and marine fish that use urea as an osmotic filler. Freshwater fish mostly excrete ammonia2,3 with only a small quantity of urea4,5"

---

Fish will pee out ammonium regardless of your claim, a quick googling will find more than enough evidence. The whole story is more complicated than my simple description but the OP asked for a simple description.

http://www.elmhurst.edu/~chm/vchembook/633ureacycle.html

Here is a longer description for anyone interested.


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## Hoppy

I'm not a chemist. But, I know that NH3, ammonia, is a gas. When it is dissolved into water it becomes ammonium hydroxide - ammonium+ and hydroxyl- (I think that latter is correct). But, gases can be in solution in water as well as being chemically combined with water. For example CO2 in water forms carbonic acid, but there is still some CO2 in solution, not combined to make carbonic acid. The pH of the water determines the amount of CO2 that remains in solution. And, the same thing works with ammonia in water. The dissolved ammonia, NH3, in the water is not good for plants. The NH4+, being a cation, is available to the plants as a nutrient.

My lecture on String Theory begins at 10:00.


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## Carson Albright

lol, I do remember reading that ammonia was a gas which only added to my confusion. Ok so this might clear things up for me. NH3= bad gas for plants, but if you put it in water it's NH4 depending on ph. So for the purposes of cycling(which is where the argument started), the majority of the ammonia recognized in test kits is indeed NH3 in concentrations of the water depending on ph? So if I had a low ph the majority would be converted to NH4, but would still have some NH3 concentrated in the water that would not be used at all by the plants. Am I on the right track?


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## DarkCobra

Carson Albright said:


> So for the purposes of cycling(which is where the argument started), the majority of the ammonia recognized in test kits is indeed NH3 in concentrations of the water depending on ph?


Not sure about ammonia tests in particular, but it's fairly common for test reagents themselves to be acidic or alkaline enough to intentionally convert the target substance into a detectable form.



Carson Albright said:


> So if I had a low ph the majority would be converted to NH4, but would still have some NH3 concentrated in the water that would not be used at all by the plants. Am I on the right track?


Let's say your pH is such that you have a ratio of 2:1 NH4 to NH3:

2ppm NH4
1ppm NH3
3ppm total

And then the plants consume 2ppm of NH4. Do you get this?

0ppm NH4
1ppm NH3
1ppm total

Nope, that violates the ratio. Instead you get this:

0.33ppm NH4
0.66ppm NH3
1ppm total

The ratio is maintained because some of the NH3 converts to NH4.

That extra hydrogen is very loosely bound. It's constantly jumping around and finding new partners. If you could view a single molecule (of either type), you'd see it transforming back and forth at an amazing rate.

It's only when you look at the tank as a whole that everything seems stable and constant.


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## Carson Albright

Ok, so I've been doing some research into the whole ammonia/ammonium thing, and cannot beleive it took me this long to find info on total ammonia nitrogen(TAN). Is this calculator accurate? From what I've read it seems like it is, but that would mean the actual percentage of NH3 in my tank would be incredibly small compared to NH4
http://www.petgoldfish.net/ammonia-calculator.html 
I keep axolotls, so my temp is kept at 18C, and I have a ph of 6.4. According to that calculator I should have .0008 ppm's of NH3 in my tank when my test kit reads 1, and as Dark cobra pointed out, there would be even less NH3 once my plants sucked up the other .9 ppm's of NH4. 
So just to get a cut and dry answer, technically I would be correct if I said plants do not utilyze ammonia(NH3) and in fact ammonia is toxic to plants. However for the sake of simplicity, because at a ph of 7(average tank ph) a temp of 25C(about average temp) and an ammonia reading of 1 ppm's it would be correct to say that plants do indeed uptake ammonia(if we're referring to total ammonia nitrogen found in the tank) because less then 1% of the actual ammonia reading is actually NH3? Just wanting to make sure I understand this fully, because honestly that seems like a lot of NH4 compared to NH3


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## DarkCobra

I was hoping someone more familiar with plant biology would reply, but I'll give it a go.

That calculator is correct as far as I know. And yes, that's a lot of NH4, which is a good thing for your fish as opposed to NH3.

Most of what you wrote can be verified by statements already posted. There's one additional thing I didn't see mentioned though.

Once anything is absorbed into a plant cell, it's in a different environment than the tank as a whole. To be honest, I'm not sure what average plant cell pH is. But I did find that when culturing individual plants cells in the lab, it's done in a medium of pH 5.7-5.8. I assume that's chosen because it's similar to a plant cell's internal pH, and what it would encounter in a plant when surrounded mostly by other cells.

At that pH, any NH3 entering a plant cell would be quickly converted to usable NH4.

I'm not sure why large amounts of NH3 are toxic to plants, but as mentioned by another poster, they're far beyond anything you'll normally see.


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## GhostRider

I had a very wise man tell me today to get rid of my bio filter in my tank, he said he works hard to make sure his filters do not build benificial bacteria.

He also told me that plants use both NH3 and NH4, although he said that they can use the NH4 easier than they can the NH3. He said this is why you try to keep your ph in your planted aquarium around 6.8. Keeping your waste in that NH4 form helping to ferilize your plants, he said this also reduces the need for so much fertilizers, and even helps your plant with co2 as they break this down.

The reason being basically this, In the planted tank the plants take care of the bio part. He said if you have to much biofiltration, then this replaces what the plants do, in turn starving your plants, and before you know it (wala) algea. So basically you would have a fish tank that you happen to keep plants in. When you have no bio filtration help, that is when you have a "planted tank" that helps its self out.

This also helps get rid of nitrates ( one of the biggest fish stressers in the aquarium). He said most test kits for nitrate are not very acurrate. That phosphate (spelling?) is needed just as badly just in small very very small amounts. when you reduce these two his plants acctually pearl from all that co2 they start rapidly absorbing and eatting all that waste too.

He also told me lots of other stuff, i learned alot to day but what i liked the most, is he is very smart in chemistry,and plants, and had a reasonable explanation for why everything happens in your tank. He turned me to a couple good books, one of which he is finishing writeing. Maybe you guys can check it out when hes done.

Keep in mind i am just learning from him so this is just the cliff notes version, so would some agree and maybe try this? i know i did. He said it helped his tank within 3 days of killing the bio filtration. 
Please leave your opinion.
Thanks for reading
Justin


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## lauraleellbp

Carson Albright said:


> Ok, so in other words plants cannot use NH3 for purposes of helping through cycling, which is what interests me. So either way if you have plants in an uncycled tank, is it safe to assume that NH3 levels will be lowered just through the use of plants, or is that an unsafe assumption?


For practical purposes, considering the tank as a whole, adding plants can only help the initial cycle go more quickly- since the goal in cycling is to be able to handle the bioload. If you start off with 2ppm of ammonia, it does not matter to the livestock whether that ammonia is converted into nitrate by the N-bacteria or absorbed by the plants; either way, the water is safe.



GhostRider said:


> I had a very wise man tell me today to get rid of my bio filter in my tank, he said he works hard to make sure his filters do not build benificial bacteria.
> 
> He also told me that plants use both NH3 and NH4, although he said that they can use the NH4 easier than they can the NH3. He said this is why you try to keep your ph in your planted aquarium around 6.8. Keeping your waste in that NH4 form helping to ferilize your plants, he said this also reduces the need for so much fertilizers, and even helps your plant with co2 as they break this down.
> 
> The reason being basically this, In the planted tank the plants take care of the bio part. He said if you have to much biofiltration, then this replaces what the plants do, in turn starving your plants, and before you know it (wala) algea. So basically you would have a fish tank that you happen to keep plants in. When you have no bio filtration help, that is when you have a "planted tank" that helps its self out.
> 
> This also helps get rid of nitrates ( one of the biggest fish stressers in the aquarium). He said most test kits for nitrate are not very acurrate. That phosphate (spelling?) is needed just as badly just in small very very small amounts. when you reduce these two his plants acctually pearl from all that co2 they start rapidly absorbing and eatting all that waste too.
> 
> He also told me lots of other stuff, i learned alot to day but what i liked the most, is he is very smart in chemistry,and plants, and had a reasonable explanation for why everything happens in your tank. He turned me to a couple good books, one of which he is finishing writeing. Maybe you guys can check it out when hes done.
> 
> Keep in mind i am just learning from him so this is just the cliff notes version, so would some agree and maybe try this? i know i did. He said it helped his tank within 3 days of killing the bio filtration.
> Please leave your opinion.
> Thanks for reading
> Justin


There's alot of problems with this. It does sound to me like the guy you spoke with probably does have a working system, but that explanation is flawed and it's very possible to achieve good results using methods that contradict these explanations...

IE- Scientific studies have shown that some plants "prefer" nitrate over ammonia. Not all plants are alike in that way. Further, the tiny difference in the amount of energy it takes to metabolize one versus the other most likely is not significant for our purposes.

You can certainly forego biological media in a filter and rely solely on plants if you want to, but if you do something to disrupt the plants (like a big rescape) that seriously puts the livestock at risk, as a tank is that much more likely to go through a mini-cycle. I personally value the N-bacteria in my filter and do my best to preserve them when I clean my filters for this reason.

It's so easy to supply N via ferts (dosed nitrates) that I just don't see the point of jumping though so many hoops to make sure tank conditions are "ideal" for ammonia uptake. And water quality in a tank where the nitrate levels are higher due to dosed ferts is extremely different (and better) than a tank where N is high due to organic accumulation. That's comparing apples and oranges.

Last but not least, I would not recommend that someone try and target a specific pH for their tank just for the purpose of maximizing plant N-uptake. CO2 levels and livestock needs are going to be more important factors to consider in regards to pH, 9x out of 10.


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## DarkCobra

GhostRider said:


> He said if you have to much biofiltration, then this replaces what the plants do, in turn starving your plants, and before you know it (wala) algea.


Biofiltration just changes ammonia to nitrate, which is a bit harder to "chew" for most plants but still a good nitrate source. More important is whether there's adequate nitrogen available, in either form. Even without a biofilter, plants can starve if there's not enough ammonia.

Otherwise, it sounds as if this fellow's describing a Walsted-type tank, or a similar variant. There's lots of them out there, and plenty of info if you or anyone else is interested.



lauraleellbp said:


> IE- Scientific studies have shown that some plants "prefer" nitrate over ammonia.


Do you have any plant names or references handy? I've been reading some scientific papers about plants that have a strong ammonia preference lately, and would like to see how the flip side works.


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## lauraleellbp

I'm trying to remember where I read that- it may have been in Ecology of the Planted Tank?

I just googled and didn't find anything immediately, but here's an interesting and somewhat related article I did find that explains why nitrates are favored in use for ferts over ammonium:

http://www.kno3.org/index.php/en/pr...10a31dc4344e=f597365d8c2afa0b3c83edafd02eb76c


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## mistergreen

I think plants prefer NH4 over NO3. Something to do with that it takes less energy to get N from NH4 over NO3. NO3 is safer for animals however.


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## Wasserpest

In European countries, many planted tankers add ammonium to their tanks, in small quantities to prevent toxicity, just like we add KNO3. They think/know/believe that plants prefer ammonium over nitrate uptake.

Regarding the ammonia/ammonium discussion, keep in mind that there is a balance, which shifts depending on the pH. Whether plants take up NH3 or NH4 isn't really that crucial. Even if they totally ignore NH3, when eating up the NH4 more NH3 turns into NH4 so the balance stays the same, just at a reduced level.


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## plantbrain

Hoppy said:


> I'm not a chemist. But, I know that NH3, ammonia, is a gas. When it is dissolved into water it becomes ammonium hydroxide - ammonium+ and hydroxyl- (I think that latter is correct). But, gases can be in solution in water as well as being chemically combined with water. For example CO2 in water forms carbonic acid, but there is still some CO2 in solution, not combined to make carbonic acid. The pH of the water determines the amount of CO2 that remains in solution. And, the same thing works with ammonia in water. The dissolved ammonia, NH3, in the water is not good for plants. The NH4+, being a cation, is available to the plants as a nutrient.
> 
> My lecture on String Theory begins at 10:00.


400 CO2 are gas and 1 is Carbonic acid. so a 400:1 ratio, very very little is actually the acid part.

For marine saltwater. I think it's a little different for FW, I recall hearing it somewhere's, and the KH play a role as well. You can bubble NH3 gas into water and kill most things pretty fast
A mixture of forms of N are optimal, not "either....... or" dicotomy that folks on these forms get themselves trapped in so very often.

Same deal with water column vs the sediments, both are ideal, not "either.... or".
Here's the paper citation link:
Pate JS. Uptake, assimilation and transport of nitrogen compounds by plants. Soil Biology and Biochemistry 1973;5:109-119

http://www.sciencedirect.com/scienc...1cbae2fa0b315d5d65df850d3672a7c7&searchtype=a

NO3 is the primary storage form. The cation that balances it is mostly K+
NH4 is not stored for any length of time in plants.
It is quickly converted to amides, ureides and amino acids. 
To best balance anion/cation balance, a mix of both forms of N is optimal.
NO2 is also immediately converted into NH4 as well.

We have fish, so there's ample source of NH4, and we have soil, also, ample NH4.
In high aerobic systems, we have ample reducing power for NO3 and the shoot/leaves can easily fix NO3.
Roots zones are better for NH4.

This is likely why we see better growth when using sediments + water column fertilizer vs "either .....or".
Such black and white thinking does not help integrate ideas well.
And...the world is rarely black and white :idea:


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## plantbrain

mistergreen said:


> I think plants prefer NH4 over NO3. Something to do with that it takes less energy to get N from NH4 over NO3. NO3 is safer for animals however.


Let's take this preference and energy in context.
What about the efficacy when CO2 is correctly added vs not with respect to N?
How might that effect things?

Light intensities differences?

Fish loads vs none/hardly any?
Fish waste and food types?
Soil source vs none?

We cannot make blanket statements without leaving ourselves open for falsehoods and myth making. We all risk this.
Relative to poor CO2 management, soil vs not, this difference between NH4 vs NO3 is minute comparatively.
*
Can folks grow plants just fine and real nice with out soil?
Without NH4 additions?

Of course.*

So why when I suggest more than say 10ppm of NO3 dose folks come along and claim we do not need to add more than this cause they can do it just fine without???

You cannot have this both ways.

There are cases where it will improve growth, and some where it will not.
the main point here is adding fish, soil etc, these are easy and safe long term source sources of NH4. Add NO3 for the rest.

Both, not "either... or".
This is the easiest management.
Still, poor CO2 use is far more the issue for 95% of folks.
Dosing is VERY easy.

As far as a rate of uptake in a med light CO2 enriched aquarium, fully plants with mix of stems and slower growing species, a max dose of 0.8ppm per day of NH4 would meet the N demands. It's dosing is more dependent and much more problematic if CO2 is not in good shape.

So you get VERY little difference for much greater risk dosing it inorganically vs say....fish or soil etc. We'd be much better off focusing heavily on CO2 management and using less light. You'll get far far more out of that than any of this.


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## plantbrain

DarkCobra said:


> B I've been reading some scientific papers about plants that have a strong ammonia preference lately, and would like to see how the flip side works.


Yes, but they lack a critical piece of missing method controls that are easy in terrestrial plants, but absent in aquatic plants: CO2.

It makes a massive difference with N, also, location of the sources and uptake sites in each organ of the aquatic plant(root vs shoot).

I do not think we can make assumptions.
We can speculate and test, but unless CO2 is also controlled for.......no one can make any conclusive arguments. This is the biggest issue with hobbyists and the whole nutrient debates.

Lack of good controls for CO2.
I've dose with both, but found little differences except where soil sources where added. for the water column, fish seem the best solution.

I've removed all traces of inverts and fish from tanks grown nothing but KNO3 dosed plants for several months, the tank looked very very nice, Erios and other wimply plants grew great. Flourite, no sources of NH4 to speak of, (some tiny % form bacteria, leaf decay/leaching, but it could not be much)

I do not see much difference.
With fish, I do tend to have subtle, very subtle, slightly different growth.
Significant? Well, if it is very subtle, then no, so I cannot say it makes a difference, but I can say it does not hurt/harm. With soils added+ water column, I can say for some species, it does make a significant difference, we can see it.


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## DarkCobra

plantbrain said:


> 400 CO2 are gas and 1 is Carbonic acid. so a 400:1 ratio, very very little is actually the acid part.


That's of particular interest to me. Where did you find that ratio?

EDIT: Nevermind, found it in Wikipedia's Carbonic Acid page.


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## GhostRider

Yes you do need nitrates, but he told me it is easy to get to many, he said seachem is the most acurate test kit to lab quality, he said on api test kits, if it reads 0 then you have plenty of nitrates, because all the other nitrates are being used so rapidly.


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## Betta Maniac

GhostRider said:


> he said on api test kits, if it reads 0 then you have plenty of nitrates, because all the other nitrates are being used so rapidly.


Huh?


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## plantbrain

DarkCobra said:


> That's of particular interest to me. Where did you find that ratio?
> 
> EDIT: Nevermind, found it in Wikipedia's Carbonic Acid page.


Google will get you.

I learned in Biogeochem class actually.
The old way:tongue:

Anyhow, the same is true with respect to NH4 and NO3.
A small amount of continuously dosed NH4 and a order or two magnitude higher for the NO3. I still do not get why folks have to be all black and white about N or nutrients/their locations in general, but give a free pass to CO2.

We cannot say much without being sure about CO2 first.


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## plantbrain

GhostRider said:


> Yes you do need nitrates, but he told me it is easy to get to many, he said seachem is the most acurate test kit to lab quality, he said on api test kits, if it reads 0 then you have plenty of nitrates, because all the other nitrates are being used so rapidly.


I think Lamotte is a bit better for the color chart alone.
Same method, but much better color reading. A reading of zero is not good nor trusted since it is at the limit of the method.
I stated this 15 years ago, and it still stands today, for the cheaper option, the Seachem is good.

In the middle range is where the method is best suited, not the extremes.
The method needs calibrated as well.

NO3's do get used up, but you might not have enough or might be limiting them strongly if the reading is really 0. Ideally, a range of 10-30ppm will be better, this provide ample removal before another dose is required, 2-3 days worth etc. 

Some tanks might only need say 1-2 ppm per day, but it is not safe to assume that all tanks and all plant species are the same with regard to NO3 and NH4 for that matter. Some will use more, others will use less, some tanks will have CO2 issues, others will not.

Some tanks have lots of fish, some do not.

Do we see dramatic differences in tanks with fish vs tanks without fish?
No, not really. So why do folks(in general, not you personally etc) harp on the NH4 vs NO3 issue?

If there was something to this for aquatic planted tanks, we'd expect to see much larger differences in tanks with or without fish.

I really have not.
Even at high rates of growth like with high light + high CO2.
I have seen it with soil, but the soil adds non limiting nutrients as well.
No one complains about them being excess or non limiting there.


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## Carson Albright

Ok, totally thought this thread had died a while ago because no one was saying anything for a while, just looked back here and am glad to see all the responses. Thanks for the confirmation, always glad to learn something new in the hobby, and at least now when someone tells me plants don't use ammonia I now know what that actually means.(after basically spending a whole snow day studying ammonia, what a nerd I am) 
I just wanna say I was not trying to spark a debate on which is better NO3 or NH4, just trying to clarify whether plants actually use NH3, which I know Tom Barr has had multiple debates about because I've read through quite a few trying to find my answer before I posted my question. 
Thanks again everyone, this has really been bugging me more than it should have been, and I'm glad to finally get this whole question settled for myself.


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## GhostRider

I agree that all tanks are different, yet the differences are little. The whole point is getting the planted tank to work. Thats the hobby and there can be many ways of doing so. I am just sharing how it worked for this guy, and the way im going to experiment with. So i cant really argue back with anything. Just wanted the opinions.


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## RadioPej

Hi guys, I thought it might be beneficial to give a rough idea here so I signed up.

Okay, so fish excrete ammonia into water. This is different from most other things, because they have all of that water for instant dilution.

Terrestrial plants in high oxygen prefer nitrate. Since most of the preferentially ammonia-consuming plants are in flooded areas, I'd say aquarium plants like ammonia too. That's an assumption. 

Now, the other part. Nitrosomonas species take the ammonia and convert it to nitrite (along the way, it's converted to hydroxylamine before the nitrite is made). Then other species like Nitrospira take this nitrite and convert it to nitrate. On land, this conversion is awesomely useful. Not sure how it works with aquarium plants though.

Even if you remove your biofilter, you'll still have ammonia-oxidising bacteria present in the tank. Yes, the filter will have the bulk of them, but they'll have formed biofilms within the tank and will still be doing their stuff. 

I think the plant will just be removing excess stuff and converting it to more useful products. It may also just place an additional load on the tank to reduce excess nutrients that would otherwise fuel algal growth.

Not sure if this helped. I'm doing my PhD in ammonia-oxidising bacteria, so I'm ok on that bit. The relation to aquarium plants not too much.


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