Another Cycle Question

[twistedlink]

Ive been reading up on nitrosoma (ammonia eating bacteria) and nitrobacter (Nitrite eating bacteria)

And it turns out ammonia inhibits growth of nitrobacter, so how can nitrobacter grow if im constantly adding 2-3ppm of ammonia to my tank every 12 hours?


My cycle started in 3 days, 5ppm to 0 ppm in 3 days, after that by the 4-th day it was going from 3-4ppm to 0ppm in 8 hours, its now been 21 days since i started my cycle, and my ammonia goes from around 3ppm to 0ppm in 7-8 hours still, but my nitrates havent gone up a single bit.

I believe my adding ammonia every 1/3 of the day is inhibiting the growth of them.

I also wanted to measure the nitrites (as they were off the chart) so i did a 75% water change, and theyre still green (API test user) and totally off the chart, so obviously my nitrite has just been adding up constantly and nothing is converting it.

I understand nitrobacter takes twice as long to colonise, but that means my cycle should have done in 9 days, its now taken 7 times as long as the nitrosoma, and nothing still.

I should have a small colony easily by now by maths alone of the time vs division of the bacteria, even if its innefficient for fish, it should still be converting say 0.5-1ppm every 7-8 hours, but its doing 0, this shows not a single bacteria is in there, so why would they randomly appear now?

Also it says pH's above 7 kill off nitrobacter, my water is 7.5 from the tap, and my tank was going down to 6.5 before i changed the water, which is ideal for nitrobacter, but it kills off nitrosoma.


Im confused, it appears nitrosoma die in acidic conditions, ammonia inhibits nitrobacter, and nitrobacter die in alkaline conditions.

So how the hell does this cycle ever finish?

Either most sources are telling absolute rubbish or im missing something here....???

After the 30th day im buying fish, if after 30 days the 2nd part of the cycle hasnt even begun 1%, it means no bacteria are in there.

 

[rabbut]

From what I remember there are 6 types of ammonia and nitrite eating bacteira, and I belive that only two are significant in aquariums, but all are commonly presant in aquariums. The ammonia bacteria group you have identifyed are correct, but the group you mention for processing nitrite does not ring a bell with me, so I belive you have the worg group. I think its nitrospira for nitrite....need to double check that, as I could be wrong...

The higher the pH the better when cycling, so a pH of 7.5 is good. At 6.5 and below, becteria growth slows. It appears that you have soft water, and this is inhibiting your cycle. Add some coral gravel or lava rock to your tank to add hardness, and keep the pH above 7.0. Allowing the pH to drop will slow the cycle, and stop bacteria processing, possibly to a point where there is a becteria die-off.

I know that it is flustrating doing a fishless cycle, and that it can seem like there is no point in carrying on when nitrite isn't shifting, been there myself. A large waterchange will help things allong well, and you have already done this.

What test kits are you using? It is possible that you have a dodgy test kit, that is giving incorrect results. I remember one member that was cycling a tank for three months believing that nitrite haden't moved due to lack of nitrate. They ran out of nitrite solution, and purchased a new kit. This new kit read zero nitrite and off the chart high nitrate, showing the tank was cycled and probibly had been for a while. Try getting your results checked by another test kit. Make sure the kit that you use for verification is a liquid kit, as dip strips are more likely to give false results.

HTH, and stick with it
Rabbut

 

[raptorrex]

Ive been reading up on nitrosoma (ammonia eating bacteria) and nitrobacter (Nitrite eating bacteria)

And it turns out ammonia inhibits growth of nitrobacter, so how can nitrobacter grow if im constantly adding 2-3ppm of ammonia to my tank every 12 hours?


My cycle started in 3 days, 5ppm to 0 ppm in 3 days, after that by the 4-th day it was going from 3-4ppm to 0ppm in 8 hours, its now been 21 days since i started my cycle, and my ammonia goes from around 3ppm to 0ppm in 7-8 hours still, but my nitrates havent gone up a single bit.

I believe my adding ammonia every 1/3 of the day is inhibiting the growth of them.

I also wanted to measure the nitrites (as they were off the chart) so i did a 75% water change, and theyre still green (API test user) and totally off the chart, so obviously my nitrite has just been adding up constantly and nothing is converting it.

I understand nitrobacter takes twice as long to colonise, but that means my cycle should have done in 9 days, its now taken 7 times as long as the nitrosoma, and nothing still.

I should have a small colony easily by now by maths alone of the time vs division of the bacteria, even if its innefficient for fish, it should still be converting say 0.5-1ppm every 7-8 hours, but its doing 0, this shows not a single bacteria is in there, so why would they randomly appear now?

Also it says pH's above 7 kill off nitrobacter, my water is 7.5 from the tap, and my tank was going down to 6.5 before i changed the water, which is ideal for nitrobacter, but it kills off nitrosoma.


Im confused, it appears nitrosoma die in acidic conditions, ammonia inhibits nitrobacter, and nitrobacter die in alkaline conditions.

So how the hell does this cycle ever finish?

Either most sources are telling absolute rubbish or im missing something here....???

After the 30th day im buying fish, if after 30 days the 2nd part of the cycle hasnt even begun 1%, it means no bacteria are in there.

cant speak for your experiences, but i can tell you doing a fish-less cycle in the way pinned here, or anywhere else come to that, will result in a fully cycled tank in around 21 days. no ifs buts or maybes! if you are having trouble, i very much doubt its the cycling method. its much more likely to be a mistake on your part, or some other variable you have not identified.

 

[twistedlink]

No my water is off the chart hard, ive just been adding 2-3ppm ammonia every 7-8 hours because it reaches 0 again.

I havent tampered with anything until this clean-out.

I use de-chlorinator, my temperature is 28-29celcius (mid 80's)

I mean the ammonia eating bacteria have colonised, so conditions are good for bacteria colonisation, it just seems the nitrospira/nitrobacter are just growing a lot slower than textbook results.

Mehhh its really expensive for another test kit lol...But yeah il get another one and see what happens, cheers.

 

[Colin_T]

I normally suggest adding it once a day and only add enough to get the level up to 5ppm.
Higher levels of ammonia inhibit the ammonia eating bacteria and high nitrites can inhibit the nitrifying bacteria.
Low oxygen levels can inhibit their growth. Make sure there is plenty of surface turbulence.

 

[raptorrex]

RDD1952
Continue to do this until your reading is 5 to 6 ppm

taken from http/www.fishforums.net/content/New-to-t...shless-Cycling/

all the information you need it right there, even comments on how to help if things go wrong.

 

[twistedlink]

Hmm okay il add ammonia just once every morning to 4-5ppm.

boboboy ive read it before, it states the nitrite eating bacteria take about twice as long, my ammonia went from 5ppm to 0ppm in 3 days, meaning it should then take 6-8 days for nitrite eating bacteria to colonise, its now 21 days, 7 times, not 2 times the length, and still nothing.

Ill buy another test kit but i dont think my test kit is faulty as my nitrites have been going up according to added ammonia, ive seen 0.25 at the start, 3-4ppm after day 2, 5-6 ppm after day 3, and then about day 12 or so it went green, and i contemplated doing a water change which ive now done, added ammonia to 4-5ppm, and just checked and ammonia is now 1.5ppm ish so i havent killed any bacteria from the massive water change and dechlorinated everything properly.

My juwel pump makes water turbulence no problem, sounds like a damn river in the room haha, and i keep the water relatively low (not too low) so that a small fountain occurs, i also keep the reflectors open at all times so oxygen can get in.

My nitrites are still sky high though (though its gone from bright green to "just turned" green on the tests so it has lowered....Im considering doing another 75% water change to bring my nitrites down to managable levels so that the high nitrites dont inhibit growth of the bacteria....

 

[backtotropical]

Hi Twistedlink,

Just to clarify for you, Nitrosomonas is the ammonia oxidising bacteria (AOB) found in our tanks, and Nitrospira is the nitrite oxidising bacteria (NOB) (I don't like that particular abbreviation for obvious reasons).

Nitrobacter is also a NOB, and is the one which was universally thought to inhabit our aquariums for many years until Hovanec proved otherwise not so long ago. Most literature you will read refers to Nitrobacter, as was thought to be correct at the time of writing. Only fairly new literature will speak of Nitrospira in our aquarium filters.

With regard to your cycle, I have never heard of high nitrite levels inhibiting the growth of Nitrospira. Do you mind sharing your source of that info? Maybe someone like Bignose could set me straight on that one?

Anyway, although i have never heard of that, i recommend that you should do large water changes to lower your nitrite to a measurable level, but for different reasons. The AOB will turn 5ppm of ammonia into 13.5ppm of nitrite (the ratio of ammonia : nitrite : nitrate is 1 : 2.7 : 3.7 or to be more precise 17 : 46 : 62), so each time you top up to 5ppm and the AOB process that ammonia, you are adding another 13.5ppm of nitrite. As you can imagine, nitrite soon reaches 100ppm+.

If you have say 13.5ppm of nitrite in your water rather than 135ppm, the bacteria will process it back to 0 quicker, and thus a big water change will allow nitrite to fall to 0 sooner, speeding up your cycle. Leaving huge quantities of nitrite in the water only prolongs the cycle and is completely unnecessary. Your filter could already be cycled and you'll have no idea as it has such a backlog of nitrite to clear. You could be thinking the nitrite still hasn't moved as it is unmeasurable with your test kit and all you see is that it is off the scale.

I agree with Colin that cutting back the ammonia meantime will help speed things up too as it will minimise the build up of nitrite. Try topping up to only 3ppm once per day, and as soon as you see movement in the nitrite, crank ammonia back up to 5ppm to give the AOB time to catch up again (it will only take 24hrs max for the AOB to catch up again as they can double in around 24hrs).

Also, crank up the temperature to between 30 - 32C and maximise surface agitation to facilitate the best possible oxygen supply.

Hope this helps mate.

Cheers

BTT