Not Cycling

[Southwoody]

Hi,

I am attempting a fish in cycle and started this 7 days ago by adding 8 tiger barbs to my 125ltr tank. The cycling process doesn't seem to be starting though in that I've taken regular ammonia readings and theyve all been less than 0.1. Nitrate is also zero whilst nitrate is a healthy 25. Correct me if I'm wrong but these seem like the kind of readings you want from a fully cycled tank.

Why has cycling not started? I did add the recommended dose of stress zyme but didn't really expect this to do much based on research. Maybe it has? Maybe the tank will start cycling soon?

The fish seem absolutely fine. I suppose they would with zero ammonia and nitrate.
Thanks for any help.

 

[SaTiVa1984]

Hi,

I am attempting a fish in cycle and started this 7 days ago by adding 8 tiger barbs to my 125ltr tank. The cycling process doesn't seem to be starting though in that I've taken regular ammonia readings and theyve all been less than 0.1. Nitrate is also zero whilst nitrate is a healthy 25. Correct me if I'm wrong but these seem like the kind of readings you want from a fully cycled tank.

Why has cycling not started? I did add the recommended dose of stress zyme but didn't really expect this to do much based on research. Maybe it has? Maybe the tank will start cycling soon?

The fish seem absolutely fine. I suppose they would with zero ammonia and nitrate.
Thanks for any help.

It has only been a week, it could take over a month to be fully cycled, just keep checking your ammonia and nitrite levels, once they start going up you will know the cycle is starting.

Nitrate is found in tap water that is probably why you are getting readings on that. (test the water for nitrates before putting it in the tank to confirm)

 

[waterdrop]

Agree with above. Keep testing morning and evening and watch out for it taking off on you suddenly.

What kind of test kit?

 

[Southwoody]

Thanks.
Looks like my cycle may be starting as I just got a 0.4 ammonia reading. I've read conflicting reports on whether to do water changes at this stage or not. Should I let ammonia levels increase before starting? No nitrite yet.

 

[SaTiVa1984]

Thanks.
Looks like my cycle may be starting as I just got a 0.4 ammonia reading. I've read conflicting reports on whether to do water changes at this stage or not. Should I let ammonia levels increase before starting? No nitrite yet.

I would leave it personally at the moment, when it begins creeping up more start doing regular water changes to keep the ammonia diluted, and the same with nitrites.

 

[ShinySideUp]

Thanks.
Looks like my cycle may be starting as I just got a 0.4 ammonia reading. I've read conflicting reports on whether to do water changes at this stage or not. Should I let ammonia levels increase before starting? No nitrite yet.

What is your pH? The lower the pH the higher you can let the ammonia get without adverse effects; this is not a linear progression though, ammonia becomes very toxic, very quickly when pH goes over 7 ish.

 

[Southwoody]

My ph has always been and still is 7.6. I think I'll monitor the fish and start water changes as soon as they show signs of stress. Thanks

 

[the_lock_man]

Thanks.
Looks like my cycle may be starting as I just got a 0.4 ammonia reading. I've read conflicting reports on whether to do water changes at this stage or not. Should I let ammonia levels increase before starting? No nitrite yet.

I would leave it personally at the moment, when it begins creeping up more start doing regular water changes to keep the ammonia diluted, and the same with nitrites.

No No No No No!!!!!!!!!!!

Ammonia, even at "low" levels like 0.4ppm is toxic to fish. Ideally you need to keep the ammonia and nitrite so diluted you can't see a result on the test at all (the filter will still cycle even with ammonia and nitrite at undetectable levels). However, to do this, you'd need to be pretty much constantly changing water. The limit, for practical purposes, is 0.25ppm.

(1) Pick a time of the day when you are always available to test and change water.
(2) Test the water
(3) If you see no ammonia or nitrite showing on the tests, leave it until tomorrow.
(4) If you see ammonia or nitrite approaching 0.25ppm, do a 50% change
(5) If you see ammonia or nitrite over 0.25ppm, do a 75% change.
(6) Test again and go to (3)

FOr more details, there's a link in signature area that's a good read.

 

[waterdrop]

yes, lockman is correct, the goal in fish-in cycling is to manually protect your fish from gill and nerve damage by figuring out the amount and frequency of water changes that will keep your poisons roughly below 0.25ppm on a continuing basis. It is more important to keep the fish safe than to attempt to speed up the cycle by giving the bacteria a higher ammonia concentration.

This brings up a worry we often hear here in the new freshwater tank section: How can the bacteria grow if we are always keeping the ammonia near zero via water changes? The easiest answer to understand turns out to be to think about what's going on in a perfectly cycled tank during all those years after the filter is already cycled. If we test the water we see a nice zero ppm ammonia from our test kit. But that's just because the kit can only see down to a certain level. Below that level there is really an effective flow of ammonia going on. The fish are giving off waste ammonia (from their gills and from their gut,) the excess food is breaking down into ammonia and the dead plant material (if any) is breaking down into ammonia and all of it is flowing in to the filter (or some of it into the plants) and being processed into nitrite and then into nitrate. The bacteria are alive and well in a cycled tank and yet the ammonia level we measure is zero ppm. Anyway, this should give you confidence that changing water during a fish-in cycle and keeping the tested ammonia level low is still going to eventually result in a nicely cycled filter.

~~waterdrop~~

 

[Steve H.]

yes, lockman is correct, the goal in fish-in cycling is to manually protect your fish from gill and nerve damage by figuring out the amount and frequency of water changes that will keep your poisons roughly below 0.25ppm on a continuing basis. It is more important to keep the fish safe than to attempt to speed up the cycle by giving the bacteria a higher ammonia concentration.

This brings up a worry we often hear here in the new freshwater tank section: How can the bacteria grow if we are always keeping the ammonia near zero via water changes? The easiest answer to understand turns out to be to think about what's going on in a perfectly cycled tank during all those years after the filter is already cycled. If we test the water we see a nice zero ppm ammonia from our test kit. But that's just because the kit can only see down to a certain level. Below that level there is really an effective flow of ammonia going on. The fish are giving off waste ammonia (from their gills and from their gut,) the excess food is breaking down into ammonia and the dead plant material (if any) is breaking down into ammonia and all of it is flowing in to the filter (or some of it into the plants) and being processed into nitrite and then into niwtrate. The bacteria are alive and well in a cycled tank and yet the ammonia level we measure is zero ppm. Anyway, this should give you confidence that changing water during a fish-in cycle and keeping the tested ammonia level low is still going to eventually result in a nicely cycled filter.

~~waterdrop~~

Agreed! You put it in a language easier to understand than the thread that I followed in the Beginners Resource Section by Bignose called "why water changes are good during cycling".
But it is well worth the read, and mathematically spot on.

 

[Southwoody]

Yes I've read this article and the advice above and am now convinced about the need to manage ammonia through water changes during the fish in cycle process.

There seems to be so much ignorance out there on issues like this. Worse than this, the fact that a number of ignorant but very persuasive people pedal such rubbish - ive read numerous articles saying that water changes are not required. Even a published book on fishkeeping i have says that to cycle a tank you simply fill it with water and leave it for 36 days i.e. no mention of the need to introduce a source of ammonia. For people like me who want to understand what's best it's difficult as not only are trying to learn but we need to decipher which of our teachers actually know what they're talking about!

 

[Southwoody]

Ok 2 weeks into my fish in cycling and I'm still getting ammonia readings of less than 0.1. Surely the cycle should have started by now!?

All 8 tiger barbs still seem fine by the way

 

[Prime Ordeal]

There seems to be so much ignorance out there on issues like this. Worse than this, the fact that a number of ignorant but very persuasive people pedal such rubbish - ive read numerous articles saying that water changes are not required.

Oh yes. The 'ignorance' doesn't get that much better here either. To be specific, there are many regular posters on this (and other forums) who roll out the worst myths of fish keeping, time and time again.

The usual ones are:

1.ammonia is converted to ammonium by dechlorinators
2.fish grown in too small tanks suffer from having their internal organs outgrow their normal size.
3.excess nitrate during cycling stalls the cycle
4.Seachem Prime is THE only dechlorinator to use, no matter what the circumstances.
5.dechlorinators do not stall cycling
6.you should only clean your filter sponges when the flow reduces substantially
7.etc..etc.

Even a published book on fishkeeping i have says that to cycle a tank you simply fill it with water and leave it for 36 days i.e. no mention of the need to introduce a source of ammonia

And that book is right...sort of.

If you just leave a tank in the sun it will naturally produce a plethora of flora and fauna, many of which will die off and produce ammonia. And it will produce ammonia in tiny amounts, just right for the sort of AOB and NOB we want in our 'cycled' tank.

It may take six weeks or so, but yes you will definitely have a cycled tank by doing nothing.

Oh, Southwoody.

If you're doing fish in cycling expect a long cycle and make sure you keep ammonia and nitrite low always, i.e. below 0.25ppm.

 

[snazy]

3.excess nitrate during cycling stalls the cycle

This is not entirely incorrect. The process of converting ammonia to nitrites to nitrates is acidifying, so the statement that excess nitrate can stall your cycle can be indirectly correct, as high nitrates means a lot of acidifying processes going on, and in turn this can lower the Ph signifficantly to a level at which nitrifying bacteria is inhibited and cycle stalls.

 

[Prime Ordeal]

3.excess nitrate during cycling stalls the cycle

This is not entirely incorrect. The process of converting ammonia to nitrites to nitrates is acidifying, so the statement that excess nitrate can stall your cycle can be indirectly correct, as high nitrates means a lot of acidifying processes going on, and in turn this can lower the Ph signifficantly to a level at which nitrifying bacteria is inhibited and cycle stalls.

No snazy, it's entirely correct (in the way I put it). You'll find countless mentions of 'excess nitrate causes a stalled cycle' on this forum. And that's just wrong.

You, however, are partially right. The ammonia to nitrite oxidation produces acid. The nitrite to nitrate does not.

So, as you say, nitrates are indirectly an indicator of a potential stalled cycle, but they are not the cause. As 'real' scientists like to say...'correlation is not necessarily causation'.