ammonium or ammonia spike

Forgot to turn the heater back on after a part change so that was 7 days in the colder weather spell,fish were fine but was having bacterial blooms so knew something was wrong.No change in fish behaviour bar the coolies intertwining their bodies together going from the bottom of the tank to the top of the tank.Done an ammonia check and came back as .25,nitrite o and nitrate 5 with PH6.6 .Have read before that when your aquarium water PH is below 7 which i have its a lot less toxic than ammonia and is converted to Ammonium which is a hell of a lot a lighter blow so how does the conversion to nitrite differ between the two,cheers..

Wheres Ian in this hour of need : )

Thanks John,the best reply you can always ever get is from the horses mouth so too speak,cheers..

There is a brief article on ammonia/ammonium equilibrium in articles here (www.irishfishkeepers.com/articles/28-hea...water-and-illinesses).

Ammonia Calculation Article

Ammonia is a weak base.........and its salt is ammonium.
Ammonium is a weak acid.

It is not a simple matter of ammonia being turned to ammonium at pHs below 7; just like it is not a simple matter of ammonia existing as ammonia at pHs above 7.

In fact, pH 7 is not a particularly important pH at for ammonia/ammonium: and so nothing especially important happens around that pH.

A more important pH for ammonia (at standard temp and pressure) would be pH 9.25.

Why is pH 9.25 important?..................... well, at pH 9.25 (well there abouts), total ammonia will exist as 50% ammonia (unionised ammonia = UA)) and 50% ammonium.

When the pH goes below 9.25 then the % of ammonium will start to increase and the % of ammonia (UA) will decrease (but not in a linear manner). It does not suddenly jump from 50% ammonia to 0% as soon as the pH becomes more acidic than pH 9.25.

Even at pH 8, at 25 Celcius, the UA ammonia will only be 1/20th (5%) of the total ammonia (total ammonia = UA ammonia plus ammonium).
If we go to pH 10 then you find (at 25 C) that the Unionised ammonia is 85% of the total ammonia.

Now, if you are using a Total Ammonia test kit then the calculations in the linked article are important.............. ie if your total ammonia is 0.25ppm at pH 8 and 25C then your unionised ammonia is going to be 5% of that (~0.013 ppm).

Looking at ammonia/ammonium............. it is an equilibrium system.
At any pH (and to a less extend, temperature) you will have x% of ammonia and y% of ammonium.
The ratio of ammonia to ammonium at the pH and temp will always try to be the same (they WILL be).
So, if something takes q amount of ammonia from the water then the equilibrium will shift such that a small amount of ammonium will be converted to ammonia so that we still have x% ammonia and y% ammonium.
Now, if you add a very small amount of ammonia to your tank (eg from a bottle) then the system will shift such that an amount of the ammonia is converted (spontaneously) to ammonium thereby keeping our x% ammonia and y% ammonium.
This is all about themodynamics and Le Chatelier's principle

Similarly, when ammonia or ammonium are being part of a biochemical reaction within a cell then the same thermodynamic principle will apply (albeit with enzymic control).

But when we look at thermodynamics within a cell then things do get even more complex as living organisms are great at doing some special chemistry.

When it comes to toxicity you have to be very careful in looking at what is being said......

ammonium is far less toxic than ammonia.
I would say that the toxicity of ammonia has been a major factor in the evolution of many animals, and a key item in the move from water to land (for land animals)..... it is not just a fish thing.

I have found (as have other scientists) that ammonia is more toxic at lower pH than it is at higher pH.............. but for a given amount of total ammonia, there is less ammonia at low pH (hence why people mistakingly believe that ammonia is less toxic at low pH...........whereas what they are seeing is simply less ammonia).

I will leave off there for now............and see if there are any questions.

This is a very complex subject.............. and that is the reason I hate the word "cycled" (as it is totally meaningless in a fish tank).

ian

Very interesting article , thanks Ian

Thanks for your reply Ian,some very interesting information of yours to try and digest.I was looking into dosing the tank with some product to rid me of the ammonium ammonia but read that some products only bind it for 24-48 hours then releases it back into the tank.Some were saying that their products deal with the ammonia and also get rid of nitrites and nitrates,i have fast growing stem plants etc that need nitrates and help to use up some of the ammonia too.What product would you reccomend to use if you know of one that doesnt remove nitrates,on a sidenote i put a few of the biohome bacteria balls in the filter to help assist in getting the level back up.
I,m very surprised i have had no fish loss and they look very healthy,maybe the fact that i run a vigorous airstone 24/7 helped to keep a certain amount of bacteria alive in the aquarium even though they would have died off in the external filter,cheers ....

Hi ,see you mention using biohome bacteria balls , are you using biohome as a filter media ? . You will have probably seen from some of my post that i use biohome ultimate in my tanks and also my koi pond , its definatly the best media out there to my mind . Just a couple of things that you might not know about it . It requires very good oxygenation , it seems to mature quite fast , finally after about 6 months it will not only reduce your nitrites to zero it will also reduce your nitrates to zero . Am not sure about the science behind this , but am sure Ian can explain , so not sure about this effect on a planted tank

Hi Robert it was you i got it from a good while back,you ordered 3kg for me and i went out to collect from your house.I have only actually filled one tray instead of more in a crystal profi e1501 a few weeks back because i wanted to see how the nitrates went.Done a water test tonight and ammonia reading is still .25 so going to do a 40 % part change yet again tommorow.Nitrates are at 0 now since last week so wondering is it coming from the tap around 5 and the plants are using them up in less than a week...

What size is your tank , just to give you a guide in my 350 tropical i have 3 trays in my 1501e of biohome , in the 470 including sump coldwater i have 15 kg of biohome , in the 1000gal pond i have 5kg in the pressure filter and 15 kg in the trickle tower i built .

Hi Robert the tank is 250ltrs running the e1501 ex and recently set up a 401 ex to take out fine particles in the water.I put the biohome media in one tray to start off for now and will fill another in a short while so theres no shock to the bacteria level.
The lay out of the filter media postions in the e1501 is wrong according to the pond guru especially when using biohome media,i recieved an email back from him a while back explaining why.With the water coming from the top sides to the bottom and up through the middle through the baskets on exit the bottom tray should have sponges,fine,medium and coarse,this is to trap the mulm first so preventing it from clogging the biohome media in the basket above to be effecive.

Hi Nomad,

You may find that amount of free unionised ammonia (NH₃) levels may be low due to the pH and the equilibrium thingy I was talking about above [....and .......just noticed that the forum has a sub-script functions now.............that is really useful]

I am absolutely not a supporter of the use of a side-effect of some water conditioner for temporarily locking ammonia out of "harms way".
SeaChem Prime is a rather good dechlorinator that happens to "lock" ammonia for a reasonably long time [many other water conditioners either don't do that at all or lock the ammonia for a much shorter time].
However, I do not feel that Prime should be used for that side-effect.

The principle of using Prime to "remove" ammonia is not actually to remove ammonia but to lock ammonia out of harms way whilst processes can act on the ammonia to convert it to less harmful chemicals (eg to nitrites by nitrosofication).
But, note, that is assuming that you have the appropriate microbial colonies active in your tank !!

I am, however, a big supporter of having an emergency supply of solid-phase removal agents in cases of emergency.

Such solid-phase things include ammonia adsorbing zeolites or nitrate adsorbing resins etc
(and PolyFilter).
There are a number of products on the market.

Now, nitrates should never to be taken to zero........... to do so is increasing the risk of proliferation of sulphur reducing bacteria in anoxic areas of the tank.
Reduction of sulphur can release Hydrogen Sulphide (H₂S)........... extremely toxic.

So.....if using powerful nitrate removers such as JBL NitraEx, take care to use it until the nitrate is lowered to a reasonable level.

Now, these are emergency measures................ and will not beat the harmony of natural processes within a reasonably mature tank.

On a bigger note, as the original question was teetering on the edge of academic stuff, the nitrogen cycle in real life is way more complex than that awful and incorrect notion of what has been in recent times called a "cycle".

Nature would not be so silly as to have a one way line and call it a "cycle" !!

Many "unexplained" fish still alive scenarios may be well explained by looking at the nitrogen cycle as it really happens or looking at the real biochemistry/biophysics/physiology of fish.

Similarly, many "unexplained" wipes out may well be due to natural things happening within the nitrogen cycle within a tank that so happen to be not what a fish keeper wants............but can still happen eg nitrates being converted to nitrites or ammonia !!

Nature is pretty tought but also so fragile.

BioHome balls....I have not used them.

ian

Yes your right about the layout . If you go to the pond gurus vidoes he has one called pimp my filter and gives a very good way of upgrading you canister filter

Hi Ian thanks again for the info,i have just done a 40% art change on the tank again PH 6.6,nitrte still at zero,Ammonia still at .25ppm and nitrate is 5ppm which was at 0ppm three days ago so i take the small rise is maybe coming from the tap water.
I was totally flummoxed when i read in your post......QUOTE ..Similarly, many "unexplained" wipes out may well be due to natural things happening within the nitrogen cycle within a tank that so happen to be not what a fish keeper wants............but can still happen eg nitrates being converted to nitrites or ammonia !! UNQUOTE .. I have never heard of this before and i would say a lot of others too
that Nitrates can be converted back,very interesting indeed,cheers..

p.s i forgot to leave the link for the bacteria balls and the filter media that they claim is the best on the market since sliced bread. filterpro.co.uk/bacteria-5-c.asp

Robert did you place sponges in the bottom tray in the e1501 external ?

Flow on the 1501e is down the side through the prefilter and then up through the filter baskets , so i put coarse , medium , and fine sponges in the bottom tray and filled the rest with biohome ultimate . Just as a matter of interest have just done water test , ammonia nil ,nitrite zero and nitŕate zero , ph 6.5 . Tank is planted with varieties of amazon sword but dose with . profito .

Thats interesting with your nitrates being zero,after reading a part of Ians post regarding zero nitrates and his vast knowledge of water chemistry amongst many other topics its making me feel very unnerving,whats that saying THE LESS YOU KNOW THE BETTER ......LOL

QUOTE...Now, nitrates should never to be taken to zero........... to do so is increasing the risk of proliferation of sulphur reducing bacteria in anoxic areas of the tank.
Reduction of sulphur can release Hydrogen Sulphide (H2S)........... extremely toxic.

In chemistry we have Oxidation and we have Reduction.
If something is oxidised then something must be reduced.
(it is all to do with donating and receiving electrons......... and that could also include loss or gain of oxygen or loss or gain of hydrogen: but I am an electron man !! ).

Nitrites are an example of a product from the oxidation of ammonia; Nitrogen gas is also a product from the oxidation of ammonia: and both of these can happen in a fish tank under the right conditions.

Now, those processes can go in reverse.
If we reduce (remember I'm talking chemistry here) nitrogen gas we can get ammonia; and if we reduce nitrites we could also get ammonia (as just one example of a product of nitrite reduction).

So....now let's look at nitrates:
Nitrogen gas is one product of nitrate reduction (we see in denitrification for example); nitrite is also a product of nitrate reduction; and ammonia can be a product of nitrate reduction: all of these can happen in the fish tank under given conditions.

Note... these are not the only products of reduction or oxidation.

One of the most common examples of nitrate reduction fish keepers see is in doing common Nitrate Tests.
Nearlly all (if not all) off the shelf wet Nitrate test kits are actually low accuracy Nitrite Test kits !!!
Within the common test kits you need to first reduce (remember.... this is chemistry talk) the nitrate produce nitrites within the test tube [usually Zinc is used as the reducing agent].
When the nitrates have been reduced to nitrite then the second part of the common test kits will measure the nitrites with a colour complex.
Magic.....??..... but wait...... that means nitrates can be converted to nitrites.........and then onto being converted to ammonia.
That can happen in your fish tank............and that can be helped by bacteria under certain conditions.

There are other products along the way in this oxidation/reduction (RedOx) system between ammonia and nitrates.

RedOx potentials comes into all of this.

Now, I said that nitrate test kits are pretty inaccurate nitrite test kits.........so a zero reading may not actually be zero.
And, a nitrate test does not need to be overly accurate or sensitive..........because they are usually nitrite test kits.

OK.............so what about zero nitrate?
well, I mean zero nitrate as opposed to 4ppm but reading as zero on a cheap test kit.

The next bit will be very rough "smoothed over" science as I want to get to an important point without the detail......
In anoxic areas of your fish tank, certain aerobic bacteria (these are not anaerobic bacteria but facultative anaerobes) can convert nitrates to nitrogen gas (=denitrification)..... these are nitrate reducing bacteria.

Now, in competition with those are anaerobic sulphur reducing bacteria.
These reduce sulphur to form Hydrogen Sulphide.
You will have sulphurous compounds in your tank as normal...........so that is the source of the sulphur.
Often, the nitrate reducing bacteria can out compete the sulphur reducing bacteria.....thereby lowering the potential for the output of hydrogen sulphide.
However, if nitrates become so low that nitrate reducing bacteria die off then hydrogen sulphide producing bacteria may start to proliferate. That is not good.

ian

Thanks Ian more to digest,in previous posts and with Roberts zero nitrate reading i was wondering what effect that would have with plant growth or lack of.Came across this small section regarding such on the filterpro.co.uk website ......QUOTE Do not worry about plant growth being affected in a tank which reads zero nitrates - the nitrate is processed into soluble nitrogen which is easily used by plants, boosting their growth.

Hi . Ian the explenation that the makers of biohome give is something to do with aerobic bacteria and anaerobic bacteria , i dont really understand but what they say is this then reduces the need for as many waterchanges , i do weekly waterchages anyway . The only thing i ask you is does this effect plant growth , which i have in the tropical tank , the coldwater tank and pond have no live plants in .them

Robert......... the media is probably some deep porous media where the outer parts receiving oxygenated water will provide an environment for aerobic microbes (eg bacteria that can oxidise ammonia to nitites, and nitrites to nitrates), and deeper in the media it will be anoxic and be an environment for anaerobic activity such as denitrification (reduction of nitrates to nitrogen gas).
Many media can do that............... some are specially made to be very good at providing the anoxic environment whilst allowing water movement through it. Maybe that what the media is that you talk about.

I did loads of work in the 70s and 80s on filter design to minimise or stop the need for water changes especially in marine tanks by removing nitrates from the water.
Yes....I had some really great systems built that could easily remove nitrates........... but I found that the lack of water changes was not great on the quality of the fish.

I presently use some even more sophisticated filtration system based upon sludge........but they have to be very very mature systems.
In some of my systems I have ammonia oxidised directly to nitrogen gas (there is no nitrites/nitrates etc etc involved).
But, I still like to do water changes.

Nomad.......... I would like to see the source of the quote.
Nitrate is a highly soluble form of nitrogen............so I don't know how it would need to be processed into an even more soluble form.

ian

Hi Ian heres the link to where i read that filterpro.co.uk/biohome-media-3-c.asp

Thanks Ian , thats a very good explanation of the process , only one point the fact that the nitrates are zero does this effect plant growth . Thanks Robert

Nomad.......... going by what is written on biohome's website, I would say that they are marketers of a product for which they show only a little bit of understanding.

For most plants is not not a great idea to force the plant into using nitrates as a nitrogen source as that compromises their energy efficiency.
But, as with anything in nature.........there are always a few exceptions.
Such exceptions are water-plantain or species of shoreweed (Littorella) that I have come across.

Most aquatic plants that I know of prefer ammonium as their nitrogen source; and would only utilise nitrates if nitrates were the only nitrogen source available.

That means that plants are an important part of the nitrogen cycle from the stand point of ammonia/ammonium removal from the water more so than removing nitrates.

However, things are never simple in real life............ you can't just think that high amounts of ammonium/ammonia are good for plants: high ammonia/ammonium is very bad for plants.........and the roots are especially sensitive to ammonium/ammonia.

I won't, yet, start talking about chemicals such as ammonium nitrate !!!

ian

Thanks Ian for related info,much appreciated ...

Here are a few pieces of published work........... the ideas I mentioned above are nothing new, and some of these "older" texts are NOT out of date either albeit that, as always, the amount of detail and additional knowledge has increased

In recent times, I have seen more and more incorrect writings on the subject appear within fish keeping literature.............. and the worse bit about some of it is that it claims to be "recent, and therefore correct" (sic) !!

For links below.......I have an Athens account, so I see some of the full articles on these links......... but the abstracts are good enough where only an abstract is available to people without the appropriate journal account:


www.jstor.org/stable/23367904?seq=1#page_scan_tab_contents

.............
www.annualreviews.org/doi/pdf/10.1146/an....pp.32.060181.001125

.....................................
This is a nice paper..
www.ncbi.nlm.nih.gov/pmc/articles/PMC2803002/

.......................................
From about page 300 onwards (esp 313 onwards)

books.google.ie/books?id=-I7pCAAAQBAJ&pr...#v=onepage&q&f=false

........................
www.sciencedirect.com/science/article/pii/0304377082900468

.............................
A full paper PDF (just the intro will do on this)
www.uam.es/personal_pdi/ciencias/solsa/Floresetal.pdf

Just a few to be getting on with.

ian

A couple of match sticks and a bucket of coffee should do the trick to get through all those links .....

nomad wrote:

A couple of match sticks and a bucket of coffee should do the trick to get through all those links .....

Food for thought when you have nothing to do.

This has been a nice thread to chat on, by the way.

It's good having these types of discussions.

ian

Likewise Ian,likewise .....

Lernt alot from this thread , thanks Ian , am going to read the links in work tomorrow night