Pesky Nitrites

[Dogson]

I won't be happy with another 20 days of this. I'm hoping with some relief from the ammonia top ups and the fact i'm cycling with some mature media may give it the kick up the ar$e it needs. Who knows it may turn blue tonight??? God i'll be like a Kid at Xmas when it does.

 

[waterdrop]

The bitter truth is that these bacteria can be very slow to grow and very random in who the pick to grow more quickly for and who more slowly, leading to some beginners being driven crazy having to listen to others for whom its going quickly! For those of you having a slow go, its important to realize though that eventually time is on your side.. they seem to simply not be able to go forever without finally at some point developing and in my opinion the ones that seemed stubborn getting there sometimes also seem the hardest to mess up later, being very solid colonies that seem to take fish additions in stride. (How's that for a positive pep talk )

OK, so if you guys want to entertain yourselves with a little "fine tuning" of your fishless cycle, here's something to think about. The whole directive of -always- dumping in enough ammonia to bring you up to 5ppm level was really a way to make our fishless cycling article considerably more simple to describe to people. The most important part of the 5ppm choice is that it be done at the very end of the process when you are finally trying to get both ammonia and nitrite(NO2) down to zero within 12 hours. At that point, getting your level up to 5ppm will guarantee large robust colonies regardless of how big your initial stocking session is.

But prior to this you can "fine tune" the amount of ammonia you add at your 24-hour marks. During the "nitrite spike" period in particular, there are plenty of advantages to adding less ammonia. For each 1ppm of ammonia added, the A-Bacs will produce roughly 2.7ppm of nitrite(NO2). Then 3.6ppm of nitrate(NO3) gets produced (I forget at the moment whether that's for each 1ppm of ammonia or each 1ppm of nitrite(NO2)!! but you get the idea.) So, assuming you're smart enough to keep your thinking caps on and go back to 5ppm later , there's nothing wrong with only dosing ammonia up to about 3ppm during the nitrite spike phase, as a way to reduce the total amount of NO2 and NO3 getting forced into the overall mix.

Of course, this -still- doesn't guarantee that overall NO2 and NO3 levels will be enough lower that you see much difference or that you avoid the pH drops that the nitric acids can bring on if you have poor buffering, but sometimes it helps a bit and there's always a small concern in the backs of our minds that the N-Bacs aren't as happy with high levels of NO2, NO3 and nitric acid pumped up in there.

So just to wrap up, if you go this route to lower your adds to 3ppm then once you are past the nitrite spike stage and you are dropping nitrite(NO2) to zero within 24 hours and beginning the long trek to it dropping in 12 hours, -that's- when to start easing the add-amount back slowly up to 4ppm and then finally 5ppm. Of course all this makes it should as if getting those kinds of amounts is easy to do and we all know its not as we are often just guesstimating a bit anyway! But that's ok, it lets you fiddle a bit more with your aquarium log and your water chemistry and keeps you entertained while you wait for those darn N-Bacs to get happy on their little stand of sponge and have babies!

~~waterdrop~~

 

[Dogson]

Entertaining and informative your Missus must love you (when you're not on TFF) I'll give it a whirl anyway

 

[alchemist]

@Waterdrop - Does 'off the chart' nitrite slow down bacteria growth - or produce a different type of bacteria like with ammonia?

If you stop adding ammonia frequently - your ammonia > nitrite bacteria colony is going to start reducing as it has no new food - I think this is the most important phase in the cycle - as you must keep supplying some sort of bio-load on a regular basis.

If high nitrite does impact nitrite > nitrate colony - then wouldn't regular water changes in this phase speed things up? and also have the added benefit of keeping the nitrate levels manageable.

Sorry to thread hijack - but I am trying to create a math model for the ammonia cycle and this is really interesting to me.

 

[arobinson1984]

Out of interest slyT, what is your tanks waters PH reading??

I didnt notice you mention it anywhere, you cycle may have stalled if your PH has dropped.

Andy

 

[SlyT]

Cheers for keeping this discussion alive, and for all the info everyone

My pH did drop a couple of weeks ago (down to about 6.4) a WC didnt help, so I broke out the biCarb. Since I have been trying to bicarb to just under 8 as I was told a pH of 8 was a sweet spot for the back development.

I think I will try and lower the ammonia additions, and maybe do a couple of WC over the WE as the level of NBacs would have to be immense to get down from the +20ppm mark.

Anyone know about the old brown pipes ? Do you experts have dirty pipes, or do you clean them out? Is the fact mine are now not translucent mean that I have done something wrong.

SlyT

 

[waterdrop]

@Waterdrop - Does 'off the chart' nitrite slow down bacteria growth - or produce a different type of bacteria like with ammonia?

If you stop adding ammonia frequently - your ammonia > nitrite bacteria colony is going to start reducing as it has no new food - I think this is the most important phase in the cycle - as you must keep supplying some sort of bio-load on a regular basis.

If high nitrite does impact nitrite > nitrate colony - then wouldn't regular water changes in this phase speed things up? and also have the added benefit of keeping the nitrate levels manageable.

Sorry to thread hijack - but I am trying to create a math model for the ammonia cycle and this is really interesting to me.

Unlike the problem with too much ammonia where 8ppm will enourage the wrong species, the problem with very high nitrite and nitrate is completely different. Even though the nitrite is "food" for the N-Bacs, they don't like living in too high a concentration of either their food or of the nitrates and they slow down their reproduction rate somewhat.

Dropping the level of ammonia the A-Bacs are seeing at this stage seems not to do any harm. Don't forget that there's still a big -time- factor to colony development. As time goes by the colony will be building better biofilms. A six-month old colony is much, much more robust than a 1-month old colony regardless of colony size per se, there are other qualities different from just size. The A-Bac colony size will be able to bounce back much more quickly late in the game when you build back up to 5ppm (just as your colony reacts to a new introduction of fish in a mature tank and increases its size withing as short as a day or two.)

Re your model, there are threads of beginners from previous years who have done quite beautiful graphs showing all the different substances throughout the process!

~~waterdrop~~

 

[arobinson1984]

I wouldn't worry about the brown pipes too much, its quite common in external filters.

If you wish to clean out the pipes you are best doing it with a brush on a long wire, the ones that are commonly used for cleaning out brass instruments.

Andy

 

[SlyT]

Thanks all,

Am I right in thinking that it is possible I do have some n-bacs, but there is too much Nitrite for them to be able to process, and that at the moment, the 5ppm per day of ammonia is either more, or almost as much as they can process ?

How can I get the nitrites down to a better level ?
What level is too high for the development process ?

Cheers SlyT

 

[Geoff1991]

Water changes to bring the nitrites down.

 

[waterdrop]

Thanks all,

Am I right in thinking that it is possible I do have some n-bacs, but there is too much Nitrite for them to be able to process, and that at the moment, the 5ppm per day of ammonia is either more, or almost as much as they can process ?

How can I get the nitrites down to a better level ?
What level is too high for the development process ?

Cheers SlyT

right, for the N-Bacs its 13.5ppm of nitrite their seeing after you put 5ppm of ammonia in and that's way more than they can process up through the nitrite spike stage, but eventually, when the spike abruptly drops, then of course they're handling that much. Fishless cycles will still proceed with NO3 at 80 and 160 and above readings of course, but afaik no one has quantified the speed deterioration they cause.

I agree with Andy about your hoses. Mine get speckled with mud too and I try to tell myself its camouflage! I clean them out sometimes like Andy describes and I'm sure there are those that make sure to do this a lot to keep them sparkling. One tip I remember reading is that every year or two, rather than going to the work of cleaning them you might as well replace them as its not expensive and they tend to lose their flexibility, which could make for a leak at some point if they slip off at one of their ends.

~~waterdrop~~

 

[SlyT]

Good Tip !

Ive just retested nitrites and with less than 10% tank water, rest tap water, Ive got Nitrites at 5ppm.

To me this looks like nitrites at over 50ppm.

Nitrates are still at about 10ppm, but as Ive said before there are quie a lot of plants in there.

How much and how frequent should I be trying to water change now ?

Is 2x50% (50% tomorrow and 50% on saturday) going to help ? should I be doing more / less ?

It looks like Im going to have to try and beg the lfs to keep my fish for a bit longer, but I dont want to push them too much. They advised that a week should be enough for all the mature media to sort it all out but I dont think that will be the case

 

[Geoff1991]

Id do one large water change of about 70-90%

Fill up, test make sure your ammonia and nitrites are at 0 then add 5ppm of ammonia and you should be good.

I have to say, after doing water changes to keep my pH up, i have been able to see my nitrites rise and fall and it just makes me feel better being able to see that nitrite is being processed.

Edit:

I started with some mature media as well after a fish-in cycle and im on about my second or third week and im still in my nitrite spike half of the cycle.

 

[SlyT]

Cheerd Goeff,

Im about to start week 7 having done 2 batches of mature media

 

[Geoff1991]

Wow, you must be sick of it...