Where Exactly Is The Bacteria At?

[TheeMon]

ive been wondering this for a while, ive had tanks since i was a little kid, been a real hobbist the last 4-5years. anyway where is this benefical bactria live at? i know its in the filter, but is it in the gravel too?

if i took the filter off one tank and put on a new tank would the new tank allready be cycled?



the reason im asking is kuz i need a 3rd fry tank and i dont got one, i got a n empty tank but its not cycled... ideas?

 

[smmetz]

From what I have read, some of it is in the gravel. However, most is in the filter. If you take all the gravel out, your tank will probably not have any noticable mini-cycle. If you take the filter media all out, your tank will almost definitly have a mini-cycle.

For just a few fry, I would take some of the filter media from your existing tank and put it in the filter for the fry tank. Well, to be more specific, I would set up the fry tank with its own filter, letting it run for a day just so the heater gets the temp stable, and extra CO2 gets out of the tap water, etc. Add the fry or eggs then. When you start feeding the fry, then get the filter media piece from your old tank and throw it in the fry filter. This makes sure there is a supply of amonia for the bacteria on the old filter material right away.

 

[k.o.d]

There will be bacteria in the gravel, but the bacteria need a constant supply of food and oxygen so the main proportion will be in the filter which meets those requirements.
If you took the filter off an existing tank and put it into a new tank all you would do is kill off the bacteria as they would have no food, but if you had fish in there then the bacteria will feed off the ammonia given off by the fish.

 

[ox5477]

I agree that bacteria exists on most things in your tank. But the proportionality to how much exists in your filter compared to everything else added together is quite high. So even if you took out all the gravel I would guess that if a cycle did happen at all, then you wouldn't even see it unless you tested the water alot, like twice a day.

If you take the filter out of your tank, you won't have a mini cycle, your tank will just begin to get loaded with ammonia, hence the reason for the filter. I guess if you had powerheads blowing alot of flow around then maybe your tank could support a few small inhabitants with enough water flow over the gravel, but I wouldn't rely on that bacteria to keep my tank going.

And yes, the reason for the bacteria grouping in the filter is water flow. Without a consistant stream of nutrition, a large population can not survive, hence only stray particles of bacteria in you gravel.

 

[edgun88]

I agree that bacteria exists on most things in your tank. But the proportionality to how much exists in your filter compared to everything else added together is quite high. So even if you took out all the gravel I would guess that if a cycle did happen at all, then you wouldn't even see it unless you tested the water alot, like twice a day.

If you take the filter out of your tank, you won't have a mini cycle, your tank will just begin to get loaded with ammonia, hence the reason for the filter. I guess if you had powerheads blowing alot of flow around then maybe your tank could support a few small inhabitants with enough water flow over the gravel, but I wouldn't rely on that bacteria to keep my tank going.

And yes, the reason for the bacteria grouping in the filter is water flow. Without a consistant stream of nutrition, a large population can not survive, hence only stray particles of bacteria in you gravel.

Hmm...I read that the majority was in your gravel, but the way you put it makes more sense. But I do have a question. In which part of the filter is the bacteria most concentrated? Is it most concentrated in the actual filter cartridge when you put your zeolite and activated carbon and that catches solid waste, or is it more in the spongy material in front of that?? Because don't you have to replace the solid waste collecting filter cartridges every now and then? Does this get rid of all your beneficial bacteria???

 

[nmonks]

The bacteria is on all surfaces to an equal depth. What matters is how much surface area there is in any given volume of substrate, and how much water and oxygen passes that substrate.

1. Filter media is, by definition, stuff with a lot of surface area. Plain gravel and coral sand can do the trick (= undergravel filters) because the grains of gravel has a fractured surface with lots of nooks and crannies for the bacteria to live. But things like filter wool, sponge, carbon, ceramic tubes, etc., are even better because they have even more complex surfaces.
2. Bacteria will grow most rapidly on places with lots of water flow carrying nutrients and oyxgen. They will not grow at all where the water flow is so low that not enough nutrients and oxygen can get there. So there are lots of bacteria in the filter, but none at all at the bottom of a deep bed of sand. The best filter designs allow air and water to mix, because this optimises the growth of filter bacteria.

So, you can answer your own question about where the bacteria are: where is the most complex media with the best flow of water? That could be (for example) inside a canister filter or the gravel if you have an undergravel filter. You also need to consider "clogging up" -- so the parts of the filter that trap solid waste lose their surface area, and consequently some of their bacteria. Typically, filters have some "disposable" mechanical filter media that can be rinsed off in hot water or replaced, and some "permanent" biological filter media that must only be cleaned gently in aquarium water.

There's no need for zeolite if you are using biological filtration. Zeolite chemically binds with ammonium. Potentially, it can let that ammonium out under certain circumstances, but most of the time it is just a waste of money. Carbon is, almost always, useless and often does more harm than good by adsorbing medications. Lots of people wonder why their anti-whitespot or whatever isn't working, when in fact its the carbon removing the medication before it has a chance to work.

Cheers, Neale

 

[edgun88]

SERIOUSLY? Carbon and zeolite aren't good for the tank? Wow thats news to me. But what if you have an ammonia spike? Is zeolite still not good? Should I take mine out?

 

[nmonks]

Yes, seriously.

Zeolite is ammonia remover. In a regular freshwater tank, the bacteria should be doing this. Zeolite doesn't work in brackish or salt water. The main use for zeolite is in tanks where biological filtration cannot be used, for example in quarantine or breeding tanks where there isn't time to set up a biological filter. Zeolite is also useful in acid water aquariums, because below pH 6, the filter bacteria cannot survive.

Carbon is not completely useless, but for most people, it is useless. In a regular aquarium, the thing carbon does -- remove organic compounds -- is better achieved by using water changes. Carbon removes organic materials indiscriminately, taking out medications as happily as organic wastes. Carbon was "invented" for aquarium use back in the middle of the last century when people thought "old" water was better for the fish. They avoided water changes deliberately, and the water went yellow. Carbon removed the yellowness. About the only time aquarists in modern days use carbon usefully is to removed medications after treating the fish. This can be useful because some fishes (and most inverts) are intolerant of medications, so the less in the water, the better.

Anyway, by default, you need neither. Get rid of them, and install ordinary filter media instead. Even plain old filter wool will be much more useful.

Cheers, Neale

SERIOUSLY? Carbon and zeolite aren't good for the tank? Wow thats news to me. But what if you have an ammonia spike? Is zeolite still not good? Should I take mine out?

 

[celaeno]

Carbon is, almost always, useless and often does more harm than good by adsorbing medications.[/b] Lots of people wonder why their anti-whitespot or whatever isn't working, when in fact its the carbon removing the medication before it has a chance to work.

Cheers, Neale

isn't that why the medication instructions say to remove activated carbon when dosing the meds?

 

[nmonks]

Yes. But lots of people don't follow that step or forget to. I made this mistake myself only last year, not realising that the filter in my tank comes with a carbon-impregnated sponge by default.

Cheers, Neale

Carbon is, almost always, useless and often does more harm than good by adsorbing medications.[/b] Lots of people wonder why their anti-whitespot or whatever isn't working, when in fact its the carbon removing the medication before it has a chance to work.

isn't that why the medication instructions say to remove activated carbon when dosing the meds?

 

[Bignose]

Zeolite is also useful in acid water aquariums, because below pH 6, the filter bacteria cannot survive.

That is not exactly true. Ammonia- and nitrite-oxidizing bacteria can exist to very low pH's, what does happen is that different species of AOB and NOB are more preferred at that low pH. So, if the pH raises again later, those acid-loving bacteria die off and you have to grow the more neutral-loving bacteria.

See Gieseke, Tarre, Green, and de Beer, "Nitrification in a biofilm at low pH values", APPLIED AND ENVIRONMENTAL MICROBIOLOGY, 2006 for a recent study of nitrifying bacteria at a pH of 4.0.

 

[nmonks]

Interesting. I've heard a different thing from someone breeding Hemirhamphodon halfbeaks at pH 5, and uses zeolite exclusively. I will try and get a hold of this paper and have a read. Thanks for the tip!

Cheers, Neale

Zeolite is also useful in acid water aquariums, because below pH 6, the filter bacteria cannot survive.

That is not exactly true. Ammonia- and nitrite-oxidizing bacteria can exist to very low pH's, what does happen is that different species of AOB and NOB are more preferred at that low pH. So, if the pH raises again later, those acid-loving bacteria die off and you have to grow the more neutral-loving bacteria.

See Gieseke, Tarre, Green, and de Beer, "Nitrification in a biofilm at low pH values", APPLIED AND ENVIRONMENTAL MICROBIOLOGY, 2006 for a recent study of nitrifying bacteria at a pH of 4.0.

 

[andywg]

So there are lots of bacteria in the filter, but none at all at the bottom of a deep bed of sand.

I am unsure of how this would apply to FW, but in SW a deep sand bed does contain bacteria, though my understanding is that the bacteria that operate in this anoxic evironment utilise nitrate and gain energy by converting it to nitrogen gas, as opposed to the sort of bacteria discussed here which convert ammonia to nitrite to nitrate.

 

[nmonks]

Andy, of course you are correct. I was talking about aerobic filter bacteria. There are, obviously, bacteria practically everywhere from inside rocks dozens of meters below the ground to floating about in clouds. The anaerobic bacteria that do the nitrate to nitrogen reaction are in deep sand substrates in freshwater tanks.

Cheers, Neale

So there are lots of bacteria in the filter, but none at all at the bottom of a deep bed of sand.

I am unsure of how this would apply to FW, but in SW a deep sand bed does contain bacteria, though my understanding is that the bacteria that operate in this anoxic evironment utilise nitrate and gain energy by converting it to nitrogen gas, as opposed to the sort of bacteria discussed here which convert ammonia to nitrite to nitrate.

 

[andywg]

Andy, of course you are correct. I was talking about aerobic filter bacteria. There are, obviously, bacteria practically everywhere from inside rocks dozens of meters below the ground to floating about in clouds. The anaerobic bacteria that do the nitrate to nitrogen reaction are in deep sand substrates in freshwater tanks.

Cheers, Neale

Ah, now this leads me to a (slightly off topic) point.

Many people warn of the dangers of fatally toxic gasses building up if a sand bed in FW is deeper than an inch or two, however by having a deep sand bed (6" or so) one can culture bacteria to aid in nitrate export.

Now I have seen tests which show that nitrate is consumed in tanks with DSB, but never seen any first hand stories of deaths from large sand beds.