Anothre Cycling Question

[Luca Brazzi]

Im currently about 1/2 way through a fishless cycle in my 75 gallon tank. Ive read post where some people have used some form of "bacteria in a bottle" to their tanks to help speed this process up, and for the most part it doesnt seem to work very well.

Ive been thinking though that there might be a way to speed up this process and maybe you folks out there can tell me what you think about it.

The typical fishless cycling process is to add ammonia to the tank, to establish an ammonia eating bacteria colony. This colony will then begin producing Nitrite which is food for the second, Nitrite eating colony of bacteria. When the second colony grows it will eat the Nitrite and produce Nitrate.

My thought was that is there a way to add Nitrites directly to the tank from the start? You know.... Nitrite in a bottle? This way I could begin growing Nitrite eaters at the same time Im growing Ammonia eaters instead of waiting for the Ammonia eaters to produce the Nitrite.

So the process would be like this:

1) Add 5ppm ammonia, and X ppm Nitrite to the water.

2) Keep adding enough ammonia and nitrite to maintain the levels until you see Nitrates. (The amount of NO2 you need to add to get Xppm should decrease as the 1st bacteria colony establishes itself)

3) Once you see X ppm Nitrates, stop adding the Nitrite completely, and only add ammonia.

4) If you can add 5ppm Ammonia and after 24 hours your ammo, and Nitrites are at 0... youre cycled... otherwise go back to step 2

This should take 1/2 the total cycle time as it would just adding ammonia since youre growing both sets in parallel.

 

[famman]

The nitrite eating bacteria grow more slowly, take longer to establish in a tank, and are less robust than the ammonia eaters. If you re-innoculate daily from a good tank, this will continually reintroduce the nitrite eaters from a robust colony. Exposure to ~ 5ppm of ammonia over extended periods of time are probably toxic to the nitrite eating bacteria. It is only when the ammonia levels drop rapidly due to the presense of a robust colony of ammonia eaters that the nitritre eaters can begin to take hold, therefore you cannot grow the bacteria colonies in parallel.
jmo
good luck

 

[Luca Brazzi]

So in otherwords, if I were to start off by adding Nitrite instead of ammonia, and I grew a large colony of Nitrite eaters without having any ammonia eaters, then started adding ammonia to grow the ammonia eaters (along with continuing to add Nitrite), the Nitrite eaters would die off?

At what concentration/exposure time does Ammonia become toxic enough to the Nitrite eaters to kill off an established colony?

 

[famman]

In short, I think the answer is yes, you'd kill off the nitrite eaters by the long term exposure to high levels of ammonia; though it would be an interesting experiment to perform.
It's JMO, and I'm not a biologist, so I'm not sure what levels/over what time span are toxic. But it does appear that 5ppm for more than 24 hours is toxic, because it isn't until this condition no longer holds true that the nitrite eaters begin to colonize.
good luck

 

[MP]

I'd seriously doubt it.

First of all, you can grow the colonies in parallel or in reverse order. People have done it. The only problem here is certain difficulties in finding a source to buy cheap nitrites.

5ppm of ammonia is far from being able to kill the second colony. Yes, some sources mention POSSIBLE suppression of the second colony by very high doses of ammonia, but I have never seen any actual trustworthy data. I realize that we can suppress a bacterial colony by high doses of anything, but the quantitative data is what interests us here.

As for the second colony being more susceptible to different types of impact, I tend to think so too. However, it doesn't mean that this is, indeed, a fact. The second colony depends on the first one in receiving food, and this relationship may lead us into wrong conclusions in some cases.

 

[wetmanNY]

While I'm waiting for the quantitative data, I am often reading posts here and there, recounting a reoccurence of nitrite in a well-established system that's recently had some measurable ammonia (medication, too many new fish, whatever). Til the ammonia-metabolizing community is producing nitrite, there's no resource available for the nitrite-eaters to be getting busy with. That would account for some observed lag in itself.

 

[Luca Brazzi]

So then the reason the second colony only establishes after the ammo goes to 0 is because thats the time when there is enough Nitrite around for them to eat. Not because there is no more ammo.

Where would one look to find possible sources of Nitrite? Chemical supplier? Ive found Sodium Nitrite on a few chemical supplier sites... I think its molecular formual is NNa02 or something like that.

 

[MP]

The second colony starts developing after the first colony starts producing nitrites. Dropping ammonia levels is a sign of it being transformed into nitrites (unless you have plants that consume ammonia directly). So the second colony doesn't need to wait till ammonia comes to zero.

Sodium Nitrite (NaNO2) is exactly what was used by those people I mentioned.

 

[JSchmidt]

I can't see any reason both colonies couldn't be grown simultaneoulsy. In fact, that's what we do with heavy seedings from established tanks when fishless cycling. If you were start from scratch (i.e., no seeding) adding nitrite right from the start would be a great idea, I think, and could conceivably cut cycling time in half. It certainly wouldn't hurt to try and report back here.

Sorry I can't help much with a source of nitrite, though...

Jim

 

[famman]

Hmmmmmm......

Very interesting. I do note that the nitrite eating bacteria generally do take twice as long to establish than the ammonia eating colony.

It would be an interesting test, take an established hob filter and isolate it. Dose with ammonia to 5ppm and continue to add every few hours for 24 hours or more to maintain the 5ppm level.
Change water and test to see if the filter is still cycled.