Dosing with Ammonia and Urea

plantbrain

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JamesC said:
Urea hydolyses to ammonia and carbon dioxide. Bacteria then convert to NO2 then NO3.

I'm presuming that the plants use the urea or ammonia before the bacteria.

James

So.............let's turn this question and observation around, why don't my tankjs and plants, as well as others, not have this stunting issue?

Answer me that. :idea:

Then you can say something.
Low NO3 and high NO3, it does take a little time, about a week or so, for the plants to adapt to highe rlevels of NO3, but this should be an issue.

I know something else is occurring because I simply do not have this issue nor have had it.
I keep Tonias, erios and then the easy to grow plants like those in the last couple of pictures.
I add 20-30ppm of NO3 via KNO3 and also have higher fish loads, that are well fed.

Why dose Urea when you can have fish?
I've done tanks without fish also, but had even better results.
This includes the Erios and Tonias etc, so called "sensitive" plants.

When everyone claimed that PO4 caused algae, I also knew they could not be right using the exact same logic I am here.
If what you suggest is true, then why does it not occur in my tanks nor has for what? 15 years or so now?

Where's the stunting and dramatic changes?

I don't see it.

I know that this idea about NO3 stunting plants is poppycock.
You need to look elsewhere and run the dosing longer than week, typically 3 weeks is a good amount.

You also have no control in your test, only an issue ;)
Until you have a control, folks still think that high PO4 = algae blooms.

When they see the tanks with high PO4 and no algae, then they know it's not PO4.
Same thing here, I have tanks, as do many others, with higher NO3, and no stunting.
Some folks using less PO4 found that they had less algae, not from the limitation of algae, rather,m the secondary effects of limiting PO4, so that the plants used less CO2. If they added non limiting PO4, then they shifted to limiting CO2.

So they assumed it was PO4, not some other factor that was suppose to be independent(CO2, maybe NO3 etc). You have the same issue here. I know you do.

I do not know why your plants are stunting, you do not either, only that what you are doing causes good growth if you add urea. I can only rule out things one step at a time, but I already did that a decade ago here...................

And since have confirmed it a thousand times over.

As folks fiddle with nutrients more and more, they have progressively trouble managing them and keeping tabs on CO2.
While CO2 is not a simple issue, adding more till your fish gasp is not what I've suggested to anyone. Current, surface movement, mist, light intensity, flow rates through the tank etc and method of measuring the CO2 all make a large difference.
ed
Measuring light also can help compare things with other folks.

Maybe it's CO2, maybe it's something in the tap, maybe it's bacteria. Unless you bother to rule things out, you honestly cannot say, I cannot either. I can only be certain that high NO3, in and other itself is not the issue.
Then I can go back and look at other alternatives. Unless you can confirm and rule things out, provide controls etc, you really cannot answer much. That issue goes way back, even really smart folks that know/knew better gloss over that.

It's fine to insist that you are right, but when I have these same plants and have 30ppm of NO3? Add high NO3, have no issues for many years.......I really cannot buy the logic. I do not dispute the observations , but that does nothing to explain why my tanks have no such issues nor others.

So it cannot be NO3 in and of itself.
there's some other issues occurring.

BTW, I have these same plants in my tanks right now.
They look mighty healthy and get trimmed often.

How can you explain those observations?


Regards,
Tom Barr
 

Sumo

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JamesC said:
I agree totally Tom. I thought for ages it was CO2 and even went to the trouble of putting a diffuser in the tank so the water flow covered the plants in micro bubbles all day. They still wouldn't grow properly. I tried for ages changing CO2 methods and flow but couldn't ever make a certain group of plants grow well. This is why I started looking elsewhere for an answer. The first time I tried the urea dosing I kept the NO3 dosing the same which is why I didn't notice any difference. This last time I reduced the the NO3 dosing right back when I dosed the urea.

I can only comment on what I see in my tank and low NO3 dosing seems to work for me. This isn't to say that CO2 hasn't got something to do with it but I think that my fish are getting a bit fed up with me whilst I'm pushing CO2 levels high. I know I'm not alone with these problems either. I just wish I had more time and money to do some more testing.

The results are quite staggering and very quick to take affect. Here is a stem of rotala rotudifolia that was initial subjected to low NO3 and urea dosing. Then I upped the NO3 and stopped the urea dosing for a while. Then I returned to low NO3 and urea dosing again. It's fairly easy to see where I made the changes.

RotalaRotundifoliaDeformation.jpg


James

Boron deficiency seems.
Best regards
 

JamesC

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Just to update this thread a bit. I'm still dosing my tank with urea and seeing no problems whatsoever with it. I'm always curious to see what commercial products use and have just seen today that the Pfertz line use Potassium Nitrate and Urea in their Nitrogen dosing solution. Pfertz are very popular in the US and come highly recommended by many people.

It appears that most of the major dosing systems use either ammonium or urea as a partial source of nitrogen in their solutions. They also use potassium nitrate as well. The list so far includes ADA, Seachem, Tropica and Pfertz. Also other specialised producers like Drak use urea, ammonium and nitrate in their Eudrakon N product. This is popular in Europe.

You may argue that the amounts may be small, but if that's the case why bother adding them at all then? I know some people will say that they just use potassium nitrate and have perfectly healthy tanks and that adding urea is pointless and risking algae, but I have seen a definite improvement in some of my plants.

If you do large water changes because you believe it lowers the ammonia levels to help prevent algae and then dose any of the above products straight afterwards you will be adding much more ammonium/urea back in than you could have possibly removed. Food for thought!!

James
 

Dave Spencer

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Well, if you are seeing an improvement James, I am definitely going to consider giving it a try.

Dave.
 

JamesC

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You do need to be more careful than when just dosing nitrate and be careful not to overdose. There have been many people who have decided to overdose TPN+ and then got into problems as ammonium levels have gone quite high.

James
 

plantbrain

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JamesC said:
Just to update this thread a bit. I'm still dosing my tank with urea and seeing no problems whatsoever with it. I'm always curious to see what commercial products use and have just seen today that the Pfertz line use Potassium Nitrate and Urea in their Nitrogen dosing solution. Pfertz are very popular in the US and come highly recommended by many people.

It appears that most of the major dosing systems use either ammonium or urea as a partial source of nitrogen in their solutions. They also use potassium nitrate as well. The list so far includes ADA, Seachem, Tropica and Pfertz. Also other specialised producers like Drak use urea, ammonium and nitrate in their Eudrakon N product. This is popular in Europe.

You may argue that the amounts may be small, but if that's the case why bother adding them at all then? I know some people will say that they just use potassium nitrate and have perfectly healthy tanks and that adding urea is pointless and risking algae, but I have seen a definite improvement in some of my plants.

If you do large water changes because you believe it lowers the ammonia levels to help prevent algae and then dose any of the above products straight afterwards you will be adding much more ammonium/urea back in than you could have possibly removed. Food for thought!!

James

I think the argument is that "some" NH4 is better than "none".
It's long been known that adding a mix of NH4 and NO3 produces the highest yields in most plants, some prefer a but more of one ratio over the other, but by and large, this is not new.

I think some have taken some of what I've said in the past about NH4 and algae a bit too far.
I know if you dose a high amount to a high light tank, I can induce algae repeatedly.
But this is only green water.

With high fish loads, eg, overloading the fish tank with high light, I was also able to do the same.
This followed with Reds and finally green algae blooms in a successional bloom over time.

We do not know what the light intensity is here. Nor the dosing rates, nor how long the dosing rates and how they where added. a mature tank should be able to withstand a decent addition of some more fish, or .....NH4 loading.
Much like fish less cycling, once the bacteria have had time, they can convert the NH4 to NO3 even without plants..........

So dosing a small amount really has less effect, if all is going well for CO2/stable light etc, if not, then this can back up and you end up with algae more than without any source of NH4(fish or from inorganic sources etc)

Now I'm of the philosophy coming at this from a fish hobbyists, which supplies all the NH4 I might need.
I like fish and is why I keep aquariums.
Plants are in many respects, a secondary hobby.
Like slowly adjusting the stocking levels, adding NH4 to a fish tank that has been fishless cycled, is the same as adding the Urea or NH4CL or (NH4)2SO4 or whatever form of salt for NH4.
Are the plants really getting the this slug dose of NH4?
Or is a lot of it going to bacteria and ending up as NO3 in the end?

Plants do best with a mixture of NH4 and NO3. Not one or the other............(which is where a lot of debates foolishly end up) Now fish cannot supply all the NO3 I might need, since it all starts off as NH4, but they can supply plenty of NH4.
They also supply it metered, slowly and continuously at lower residual dosage than most even the best dosing pumps might.

So if you have fish, there's ample NH4 dosing right there.
Top it off with KNO3...........

Seems like the best management and the least risk to me given the choices/trade offs.

Adding NH4 to commercial mixtures is done for a couple of reasons, it's cheap, it's also often used at low ppm's for hydroponic fertigation, too much NH4 ends up burning terrestrial leaves and mist grow out systems.
This is the same for ornamental plants for landscapes as it is for aquatic plants, they are grown in very similar fashions commercially.

Virtually all aquatics like some NH4 and NO3, they serve different and similar roles, NO3 is the main anion inside the tonoplast which helps to drive growth, turgor pressure and ionic balance, NH4 is the easier form of N to assimilate into amino acids, but NO3 is a better long term supply and can be dosed at high rates with less loss due to bacteria transformations etc.

Rather than the thinking of either/or, using both works well.
If you lack fish, then adding it is likely wise(an option), but otherwise, simply feed fish well and have decent stocking level.

James, what is your stocking levels and what types of fish food and frequency do you feed?

I'm loaded with 0.5 Amano shrimp per gal, 0.5" of plecos/catfish, then 1 per gal of tetras/schooling fish.
I'm feeding 3x a day, flake,. sticks and a mix of bloodworm, mysis, brine 2x a day.

That's a fair amount of NH4 coming in, with the assumption of 10% retention in the fish per N added via from fish food.

Adding a small amount, you can go to 0.8ppm per day of NH4 without issues I think, without any fish, should result in improved plant growth I would predict. If you add too much light, mess up CO2, then the chances of messing the system are higher, but that assumes dependence, not independent results with NH4 in and of itself. It also assumes that fish and shrimp are not adversely affected by inorganic dosing of NH4.
Food comes in bound, then is excreated slowly to urea/NH4.
So the total exposure is much less.
Still, in a well run planted tank, the dosage should not cause harm, it's when poor management occurs, then the NH4 could be toxic, much more so than NO3.

I'm not so sure you get that much out of the NH4 dosing really.
I've had tanks do extremely well with no fish and no NH4 dosing or snails or any other smaller criters as a source of NH4.
Just dosed NO3 as the sole source, grew Erios, every sort of picky stem plant etc.

No issues at all.

But.........I like fish, so they are in all my aquariums.
Still, I think some misconceptions have come about with some things I've said regarding algae and NH4.

Dose makes the poison, not complete absense/presence.
I have plenty of NH4 in my tanks, but in a different form/method: fish. These tanks also will go downhill much easier than a tank without fish/ withoutNH4 dosing also. So the dependence on other factors like CO2/lighting are no different than inorganic dosing of urea/NH4.


Regards,
Tom Barr
 

emreutku

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Hi james, i read your write-ups and Ä° like very much, also i like brilliant ceg4048 and mr. Tom Barr as always.
I want to ask does 0,5ppm NO3 and 0,5ppm urea add the same amount of nitrogen to the tank?

I read the seachem nitrogen (derived from potassium nitrate and urea),
http://www.seachem.com/Products/product ... rogen.html

""
According to seachem;
One-half of the nitrogen in Flourish Nitrogenâ„¢ is from nitrate so you can get a reasonable estimate of nitrogen levels by doubling a nitrate reading...

Direction;
To target a specific nitrogen increase, dose according to the following formula: 0.25vn=m, where v= volume of tank in gallons*, n=desired nitrogen increase (if using a “nitrate equivalent” value for “n” then use a factor of 0.05 instead of 0.25 in the formula) and m=volume of product to use in mL. For example to raise 20 gallons* by 0.20 mg/L nitrogen you would use: 0.25*20*0.20=1 mL. ""

what does it means?

****

In Turkey there is available a very cheap product among the others called " mircobe-lift bloom and grow"
This product contains %10 urea, no phosphate and and contains other micronutrients also.
Can we use ıt in out high tech planted tanks?

thanks and regards
 

plantbrain

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No, they do not add the same amount, it depends on the measurement units used, N as Urea or N and NH4, are different since you need to other parts of those ions.

You should be able to use that product without issue in Turkey.
I think using NH4 via the sediment is the way to go, after that, fish waste, finally, dosing it via a solution.

All work, but sediments add a much higher % and that are non toxic but still available to plants.
This last only about a year, so fish waste is good as well, water column needs dosed at smaller % and lot can be removed via bacteria transformation. I do not think aquarist get that much out of urea vs NO3 in % growth in the water column.

If KNO3 is too tough to find, or urea is cheaper and available, not really an issue, problem is that over the years, folks have gotten really wild with KNO3, I would not suggest wide spread use except in very small amounts for planted aquarist, they will lard it on and kill fish and burn things.

Commercial liquid aquarium products are very very dilute, mostly water, with a tiny bit of ferts added, so the % NH4 is still pretty small, the sediment holds roughly 20-2000X more NH4.

I think adding say 1:3 ratio as far N from NO3 vs NH4(as N, not ions) is fine in most solutions.
So say a 10ppm of NO3 and say .7 ppm of NH4 per dose is the upper limits.
You might be able to cut this in 1/2, say 5ppm and .4ppm of NH4 if you did this once every other day on a moderately lit tank and get good results.

I like sediments as the source though.

Regards,
Tom Barr


Regards,
Tom Barr
 

snobi

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Regards,
Tom Barr
regards to everyone, btw tom haven't you tested it yourself using UREA as for test? and see the difference with the other one?, i don't have a budget to try out the test but i will give it a shot since it was cheap here in the Philippines (KNO3 is hard to come by + plantex csm+b is also hard to find and badluck nothing at all.), i also post a question of how much urea is safe to dose,

I'm going to test this 0.5ppm to my 50gallon tank and see a different in 3 to 4 weeks.

regards,
Roy
 

micheljq

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Hello, very interesting thread,

If dosing UREA gives this reaction : CO(NH2)2 + H2O + urease -> 2NH3 +CO2

Does it mean we could use it to dose carbon (co2), instead of the pressurised co2 systems? CO2 is not cheap here. I see an interest because it brings co2 in the tank. However i am fearful of the NH3 it creates. I might as well dose UREA and stop using my co2 cylinder.. but i fear for my little fishes.

Michel.
 
Last edited:

dw1305

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Hi all,
Does it mean we could use it to dose carbon (co2), instead of the pressurised co2 systems?
No.
However i am fearful of the NH3 it creates
Yes that is the one, toxic amounts of NH3 long before you get to appreciable amounts of CO2.

One of the original ideas behind soil substrate tanks was that the break down of organic matter would supply CO2 to the plants, and this was one reason for having limited water movement. Problems come because the decomposition processes deplete oxygen.

I'm not a CO2 (or carbon supplement user) but is "liquid carbon" (glutaraldehyde based) an option?

cheers Darrel
 

Manuel Arias

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I'm not a CO2 (or carbon supplement user) but is "liquid carbon" (glutaraldehyde based) an option?

Within the time, and more and more convinced that glutaraldehyde based products are just a complement of normal CO2 injection. Some plants that are very bad to uptake HCO3- or CO2 dissolved in water can benefit of this. But I strongly doubt that products like Exel can replace CO2 injection. I see more a synergy than a replacement strategy with them.

Cheers,

Manuel
 

zozo

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I've used little bit of regular 2-2-4 fertilizer you would use for garden or potted plants for a while in the tank to supplement the tropica dose a bit extra with N. 1 week Tropica the other week the 2-2-4. It contained 0.5 % - NH4 and 2% - NO3.. Had medium light at the time and very rappidly a nice green carpet of alga attaching to the substrate. Which went away again after stopping it and reducing the light.. Only a little bit like every other week 2ml on 100 litre was enough or maybe to much. :) Nasty stuff.

Now i'm dosing KNO3 with KH2PO4 and back to former light schedule, plants do beter and it seems to reduce algae growth.
 

oviparous

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Been dosing urea, daily, for some years, and i'm glad i once started it.
Some plant react very good (better colour, bigger leafs), others don't seem to care.
I'm now dosing 2 x 0,25 mg/l a day, hoping the urea will last longer before being processed by bacteria
than 1 dose of 0,5 mg/l.

If dosing UREA gives this reaction : CO(NH2)2 + H2O + urease -> 2NH3 +CO2

Does it mean we could use it to dose carbon (co2), instead of the pressurised co2 systems?..
I see an interest because it brings co2 in the tank.
The impact of it if processed by bacteria would be, like Darrel pointed out, practically none.
But i am curious how a plant uses the CO2 when urea is taken up by the plant, and processed inside the plant. Would the CO2 be transported to the Calvin cycle, used in another way or dumped out of the plant?
 

Manuel Arias

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But i am curious how a plant uses the CO2 when urea is taken up by the plant, and processed inside the plant. Would the CO2 be transported to the Calvin cycle, used in another way or dumped out of the plant?

This is a hard question. Thinking about the plant metabolism, I would say that anabolism of urea to retrieve ammonium happens at a different point than photosynthesis. For instance, photosynthesis fixes the carbon but this is partially burnt to produce energy that also generates CO2. That energy is then employed for other catabolic reactions, like assimilating nitrogen to form amino-acids and then proteins. The process with urea seems to be not different from what happens during breathing, so CO2 generated at such point will be more likely released to water.

There is, however, an exception. Some aquatic plants have an adaptation in order to improve CO2 absorption for photosynthesis, which is called aerenchymas (see photo below). These are mainly (but not only) thin tubes running all along the plant, some times connecting even leaves and roots. These aerenchyma are empty space, with no water, but filled with gases. These gases are mainly oxygen and CO2, which comes from the plant activities and, in some cases, because the plants use this to absorb CO2 at root level and transport it to the leaves where the photosynthesis happens. In this occasion, plant is actually pumping the byproducts of its metabolism (both CO2 and oxygen) to these spaces so they can recycle it. Obviously this is just a part of the whole volume of gases being generated, but it is a good contribution in many species. These aerenchyma are the source of bubbles some people observe when trimming some plants (e.g. Eleocharis acicularis). A secondary function of the aerenchymas are to add buoyancy to the plant, helping to keep the tails straight towards water surface and then allowing thew plant to need less structural molecules to keep the plant in position. The weight of this part, however, it is very specific for each species.

Cheers,

Manuel

Aerenchyma2.JPG
 

roadmaster

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Photo look's like my arteries according to the Doctor.:oops:
Two heart attack's and four stent's, and I'm still among those above ground.:thumbup:
 

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