Nitrifying Bacteria

[Miss Wiggle]

No worries, a friend pointed out the post and I looked around the forum and its seems pretty interesting so I decided to speak up.
I actually don't post at other forums but I do visit a few others.

well i'm certainly flattered that you find our forum interesting enough to speak up. I certainly like it here

There are several factors that determine whether a mix will work. First off - the mix has to have the right bacteria for the aquarium environment. This seems simple but it is not. Just because an ammonia or nitrite-oxidizing bacteria works in the lab, in a flask or petri dish does not mean its is going to work in the aquarium. Many people seems to think that a nitrifier is a nitrifier is a nitrifier but that is not the case. These bacteria have preferences - just like your fish. You wouldn't put a goldfish in a saltwater tank and expect it to live so why would you expect that one bacteria species will live and thrive in all aquatic environments?

So right off the bat many people say "any mixes are worthless" based on experience with mixtures that have no chance of working because they have the wrong bacteria. Now assuming the mixture has the right bacteria the mix has to be treated right - which means no freezing (that kills the nitrifiers instantly) and the temperature should not get above 100 deg f (38 deg C) - these bacteria, especially the nitrite-oxidizing bacteria to not like these warm temperatures.

The next factor is maybe the hardest to understand - a lot of people want to think of bacteria as people too - meaning that if a person does not eat he/she will eventually die. This is not the case for bacteria - they are genetically programed to go through very long periods of time in bad conditions (meaning for nitrifiers no ammonia or nitrite). What is true is no bacteria gets 'better' in the bottle. Their activity and ability to react gets less and less over time. So it important to make sure they are in the best condition when first put in the bottle - this is a quality control function of the company bottling the bacteria. How a company might do this is maybe beyond this discussion but it is an important factor.

However, refrigeration slows down the rate at which the bacteria lose their ability to respond. Think of the bacteria as a re-chargeable battery - the more charge they have when they go into the bottle the better and the slower the charge dissipates the longer the bacteria will be good in the bottle. Well the best way to slow the dissipation is by refrigeration. The bacteria will not die if at room temperature for a few months but their charge dissipates faster than if they were kept in the refrigerator.

Thanks Tim,

that makes sense, can you clarify a few things further please....

You've said the bacteria shouldn't freeze and shouldn't go above 38oC, whats the actual minimum temp, is it freezing point or will a lower temp but not quite freezing damage them?

When you say they can go 'long periods' without food, how long are we talking (assume kept in refirgerated conditions)?

I can understand the analogy of not putting a goldfish into a saltwater tank and expecting it to all be OK.

We know or have theorised through our experiences some of the conditions which can make the bacteria thrive, tanks always seem to cycle faster if you can get the pH up near to 8, likewise a temp of around 30oC seems to be optimum. Can you make any suggestions for other factors (got to be things the avergae home aquarist can test for as if we can't test for it we can't control it) which give the bacteria a better chance of working. So if people want to go out and make use of a bacteria in a bottle product, is there anything practical that they can do to swings the odds of sucess in their favour?

 

[LauraFrog]

I had a couple of questions too... lol!

You say basically that nitrobacter is not the main nitrifying bacteria species in aquaria because it thrives in a high nitrite environment. If somebody added living cultures of nitrobacter to a tank and then fishless cycled it, would they survive with the small amount of nitrite if they can survive without food?

The stuff the eco start is in claims to be a 'porous mineral base'. It doesn't smell like skim milk! I have no idea what it is. I should see if it's a pH raiser, it must be if it's limestone. I can't believe I never thought to test. I'm back from the titration competition, 'souvenired' about eight plastic pipettes and a plastic vial. All disposable, it would have got the chuck anyway! lol. but I couldn't nick the hydroxide. It was too weak (molarity 0.1114) Does anybody know the concentrations of the sodium hydroxide used in the Nutrafin (Hagen) ammonia test? Bottles one and two? I'm trying to recreate it for less money because I'm sure I can get the chemicals elsewhere. The problem's going to be the phenol.

 

[rhostog]

...

Does anybody know the concentrations of the sodium hydroxide used in the Nutrafin (Hagen) ammonia test? Bottles one and two? I'm trying to recreate it for less money because I'm sure I can get the chemicals elsewhere. The problem's going to be the phenol.

Hi LauraFrog - The Nutrafin ammonia test (A-7821) I've got just uses one bottle, so it's obviously different from yours (I'm in the UK) - but the 'hazardous' ingredients of their test kits are given in the safety data sheets which you can track down on their website. [URL="http/www.hagen.com/uk/safety.cfm"]http/www.hagen.com/uk/safety.cfm[/URL]
There are other ammonia test solutions shown which might match yours (7858 contains phenol and 7856/57 contain sodium hydroxide). Not sure if it gives enough info for you though.

 

[DocTim]

Hey All:

Corleone - I will wander over to the scientific section and jump in where I can. I think a lot will interest me, I was (am) a hobbyist before I became a scientist and find that there are a lot of interesting things that come up in the hobby. I can't promise to post everyday (I can say I won't) as I travel a lot but I will chime in when I can.

Miss Wiggle -

You've said the bacteria shouldn't freeze and shouldn't go above 38oC, whats the actual minimum temp, is it freezing point or will a lower temp but not quite freezing damage them?

It is the water becoming ice which forms water crystals that puncture the cell wall of the nitrifier, killing them. The exact temperature this occurs will depend upon the water conditions.
But we can make it simple and say when the water freezes

"When you say they can go 'long periods' without food, how long are we talking (assume kept in refirgerated conditions)?"

At 10 deg C (50 deg F) I have had bacteria remain active for up to 2 years in freshwater. A lot depend on the storage conditions and the shape of the bacteria when they were put in the refrigerator.

We know or have theorised through our experiences some of the conditions which can make the bacteria thrive, tanks always seem to cycle faster if you can get the pH up near to 8, likewise a temp of around 30oC seems to be optimum. Can you make any suggestions for other factors (got to be things the avergae home aquarist can test for as if we can't test for it we can't control it) which give the bacteria a better chance of working. So if people want to go out and make use of a bacteria in a bottle product, is there anything practical that they can do to swings the odds of sucess in their favour?

My recommendation would be to keep the water warm (30C is good) the pH high (8.0 to 8.4) and make sure there is some alkalinity - a lot people confuse pH and alkalinity they are not the same. Also the nitrifiers like iron (the reason they look red) so a little iron helps. The biggest problem is the chlorine-chloramine-ammonia removing products that people use. Some of them really set back the nitrifiers - why exactly I do not know but I know from practical experience some brands inhibit the nitrifying bacteria.

LauraFrog - the sodium hydroxide concentration for the phenol test is 6N. You want to get the pH above 12 to do the testing.

You say basically that nitrobacter is not the main nitrifying bacteria species in aquaria because it thrives in a high nitrite environment. If somebody added living cultures of nitrobacter to a tank and then fishless cycled it, would they survive with the small amount of nitrite if they can survive without food?

There is a difference between surviving and thriving plus, in the case of Nitrobacter their 'food' is nitrite, I guess I don't quite understand if you are saying nitrite is not their food.
I know it sounds like I am splitting hairs but if you add Nitrobacter it will not die (therefore it survives) but it is not 'working' so not growing and replicating (thriving) and so after a while the numbers of nitrobacter cells are too low to measure. Remember with all these test there is a lower detection limit so one can only say that Nitrobacter was not detected but you can't say it is absolutely not there. Also just because one detects a particular bacterium does not mean it is the one doing the work. You have to show that the bacterium you are studying is the one actually performing the process (in this case nitrite oxidation).

thanks all for the warm welcome and questions

 

[Miss Wiggle]

We know or have theorised through our experiences some of the conditions which can make the bacteria thrive, tanks always seem to cycle faster if you can get the pH up near to 8, likewise a temp of around 30oC seems to be optimum. Can you make any suggestions for other factors (got to be things the avergae home aquarist can test for as if we can't test for it we can't control it) which give the bacteria a better chance of working. So if people want to go out and make use of a bacteria in a bottle product, is there anything practical that they can do to swings the odds of sucess in their favour?

My recommendation would be to keep the water warm (30C is good) the pH high (8.0 to 8.4) and make sure there is some alkalinity - a lot people confuse pH and alkalinity they are not the same. Also the nitrifiers like iron (the reason they look red) so a little iron helps. The biggest problem is the chlorine-chloramine-ammonia removing products that people use. Some of them really set back the nitrifiers - why exactly I do not know but I know from practical experience some brands inhibit the nitrifying bacteria.

yeah we have a lot of people having problems cycling and find out that they're using zeolite or something like that in their filters, soon as they take it out the cycle starts up. it's a right old pain.

The iron one is new to me and certainly interesting, I'm guessing the easiest practical way for us to achieve this is to use a plant fertiliser in cycling tanks........ very curious to try this now and see if it makes any tangible difference...... right who'se got a cycling tank and wants to try an experiement?

more nosey questions...... what fish are you actually keeping now? got any pics of your tanks?

 

[Corleone]

I actually have two cycling tanks right now, but I think they're both too far along to really test. Both are just about half done, I think I'll add a normal dose of Flourish to one and see if anything spectacular happens.

 

[Miss Wiggle]

I actually have two cycling tanks right now, but I think they're both too far along to really test. Both are just about half done, I think I'll add a normal dose of Flourish to one and see if anything spectacular happens.

give it a shot and see what happens anyway! Flourish shouldn't do any harm so I reckon it's worth a shot.

 

[LauraFrog]

Noob question - what IS the difference between pH and alkalinity?

At the titration comp yesterday I was reading this poster on the wall about chemical first aid. There was a specific set of instructions for phenol poisoning and quite a lot of chemicals listed as phenols. Does anybody know which one is used in the tests?

 

[Corleone]

Noob question - what IS the difference between pH and alkalinity?

Alkalinity is part of the hardness (Carbonate hardness to be specific) of the water, pH is the activity of dissolved hydrogen ions in the water. They are closely related, Miss Wiggle has a link in her sig about it that I haven't read, but it might explain the relationship in better detail than I can.

 

[backtotropical]

Noob question - what IS the difference between pH and alkalinity?

pH is the measure of how acid or alkaline something is.

Alkalinity (you can see why it can easily be confused) is the capacity of the water to resist a change in pH. This function is performed by what is known as 'buffers'. Calcium carbonate is the most common 'buffer' in aquaria. Alkalinity is measured by the kH scale (carbonate hardness aka alkalinity). To summarise, alkalinity is the degree of ability to resist a change in pH.

HTH

BTT

edited to say: I'm not the most scientific member on TFF, but that is my understanding. I'm sure DocTim will verify or correct me.

 

[LauraFrog]

So if I get a litre of water with high alkalinity and then a litre of water with low alkalinity and both have a pH of 8.6 and then I dump an equal amount of sodium phosphate in each, the one with low alkalinity will end up with a lower pH?
I'll go find that thing in MW's sig as well.

EDIT: Is alkalinity another term for kH? If it is I know what that is.

 

[DocTim]

Hey All:

pH is the measure of how acid or alkaline something is.

while this a typical 'aquarium' definition it, IMO, is not very helpful (no offense intend) because one can measure pH but how does one measure 'acid' or "alkaline". The proper definition of pH, which is not hard to understand, is that the pH is the measure of the Hydrogen ion activity (concentration) in water.

That's it - basically how many hydrogen ions are in the water. At a pH of 7, neutral, there are just as many hydrogen ion (H+) as there are hydroxyl (OH-) ions. Because the pH scale is actually negative the more hydrogen ions there are the greater the number as in -6, or -5 etc (how's that for confusion!) and just to make it more fun the scale is logarithmic! So at a pH of 6 there are 10 times more hydrogen ions that at a pH of 7.

Alkalinity (you can see why it can easily be confused) is the capacity of the water to resist a change in pH. This function is performed by what is known as 'buffers'. Calcium carbonate is the most common 'buffer' in aquaria. Alkalinity is measured by the kH scale (carbonate hardness aka alkalinity). To summarise, alkalinity is the degree of ability to resist a change in pH.

The above is generally correct - it is the resistance to change in pH. But what chemical(s) contribute to this resistance? In the vast majority of aquaria the two chemicals are carbonate and bicarbonate (calcium, magnesium do not contribute to alkalinity). This is why it is also called Carbonate hardness - because of the carbonate element!

DrTim

 

[LauraFrog]

So alkalinity IS called carbonate hardness. I get it now. Read up on that ages ago....

I'm still trying to get something underway with the fish tanks at school. The whole 'stick aquariums in the science classrooms' was the brainchild of the science head of department who is also my science teacher. He wants to put some life in there - a stunning display of nature sort of thing. I'd be happier if he'd let me get a big paludarium in there, but obviously we're on a budget. He is extremely busy, so I've offered to do the setup and maintenance and sort out the ordering of the stuff we need, provided he pays for it all. (There's something in it for me too - because the school is not a 'member of the public' we can order directly from wholesalers and there's nothing to stop me annexing a few things I want to the order and paying him back.)

I think he would also like to turn it into a bit of a project for the advanced science students. So obviously I'll be printing off a heap of stuff from the scientific section and possibly from this thread as well. There's a lot more to aquariums than filling a glass box with water and putting some fish in it, as the senior science students (who don't keep fish themselves and thought this would be a hoot) are going to work out. It was so funny, on the bus I was talking to one of the science teachers, bitching about wrecking the phenol and yapping about cycling. They caught me taking notes in a lecture as well. They looked sort of surprised when they realised I was talking about fish tanks the whole time when they thought I was on about some kind of senior level chemistry.

 

[backtotropical]

Hey All:

pH is the measure of how acid or alkaline something is.

while this a typical 'aquarium' definition it, IMO, is not very helpful (no offense intend) because one can measure pH but how does one measure 'acid' or "alkaline". The proper definition of pH, which is not hard to understand, is that the pH is the measure of the Hydrogen ion activity (concentration) in water.

That's it - basically how many hydrogen ions are in the water. At a pH of 7, neutral, there are just as many hydrogen ion (H+) as there are hydroxyl (OH-) ions. Because the pH scale is actually negative the more hydrogen ions there are the greater the number as in -6, or -5 etc (how's that for confusion!) and just to make it more fun the scale is logarithmic! So at a pH of 6 there are 10 times more hydrogen ions that at a pH of 7.

Alkalinity (you can see why it can easily be confused) is the capacity of the water to resist a change in pH. This function is performed by what is known as 'buffers'. Calcium carbonate is the most common 'buffer' in aquaria. Alkalinity is measured by the kH scale (carbonate hardness aka alkalinity). To summarise, alkalinity is the degree of ability to resist a change in pH.

The above is generally correct - it is the resistance to change in pH. But what chemical(s) contribute to this resistance? In the vast majority of aquaria the two chemicals are carbonate and bicarbonate (calcium, magnesium do not contribute to alkalinity). This is why it is also called Carbonate hardness - because of the carbonate element!

DrTim

Thanks DrTim,

I've learned something today. I was almost right!

May i suggest that we should start a thread in the scientific section, maybe titled 'Aquaria Filter Bacteria Discussion' or something similar?

We may be more inclined to get input from some of the more scientific-minded members over there. Could get very intreresting!!

LauraFrog, theres a link in my sig to the pH/kH discussion if you want to read on further. Maybe DrTim would like to contribute to that one too?

BTT