New Cardinal Tetra's

[leighton_87]

Hi
It is a new tank. Cycled for 6 weeks from boxing day and the lemon tetras went in 8 days ago. I had been given different advice from lots of different people on how to stock after a fishless cycle. Some said that I could fully stock the tank with confidence, others said I should stock gradually. In the end, most people were saying to stock gradually so that's what I decided to do. I was also advised on here that I could stock one species at a time as long as I left 1-2 weeks between adding new fish and also assuming the water tests came back clear.
Mikey1, refarding my bacteria not being able to cope with the bio load if I add fish too quickly, forgive me as I am a beginner but if my bacteria was processing 2.0ppm of ammonia and nitrites were clear after 12 hours during my cycle, and since adding the first 7 fish ammonia and nitrite have been zero every day, would that not suggest that my bacteria is coping?
Livewire88, thanks for the info. I will keep a close eye on the remaining 5. I wasn't intending on adding any more fish for another 2-3 weeks so this will be a good bit of time to see how things progress. Either way, I won't add anymore Cardinals for a long time.
I appreciate your replies guys.
David

I know the topic has moved on now but unjust wanted to provide clarity on the b g able to fully stock after a fishless cycle.

In theory if you arendosin to 5ppm you are creating more ammonia than a fully stocked tank and therefore have sufficient bacteria to sustain a full stocking. However by adding the lemon tetra and nothing else you have reduced the bio load since the fishless cycle and some of the bacteria you had developed will have starved a died off. You can only keep sufficient bacteria alive to cope with the current bioload. From this point you need to stock slowly.

On top of this you should consider the fact that some species do not cope well in immature tanks even if cycled - many species are not recommended to be added to a tank less than 6 months old.

I wish you look with your tank

 

[David J]

Hi Leighton,

What you say certainly makes sense. Do you know if there is a way to tell when or if your filter has enough bacteria to cope with a new addition?

Since adding the 7 lemon tetra, ammonia and nitrite have tested zero consistently which tells me that there is enough bacteria to cope with the current stock. How would I know when to add more fish? Is it just a case of adding and then testing. Surely not because if there isn't enough bacteria you are stuck and in essence have to do a 'fish in cycle'.

Which also makes me wonder why bother doing a fishless cycle in the first place? Should you fully stock straight after cycling? If it is the case that any bacteria over and above what is required to process any given bioload will die off, and, where the general consensus is not to fully stock straight after cycling then why bother with a fishless cycle? I understand that it is better for the fish opposed to a fish in cycle but why build a certain size of bacteria colony just to let it die off by stocking gradually?

I don't intend on fully stocking but just asking the question.

Cheers

David

 

[eaglesaquarium]

Hi
It is a new tank. Cycled for 6 weeks from boxing day and the lemon tetras went in 8 days ago. I had been given different advice from lots of different people on how to stock after a fishless cycle. Some said that I could fully stock the tank with confidence, others said I should stock gradually. In the end, most people were saying to stock gradually so that's what I decided to do. I was also advised on here that I could stock one species at a time as long as I left 1-2 weeks between adding new fish and also assuming the water tests came back clear.
Mikey1, refarding my bacteria not being able to cope with the bio load if I add fish too quickly, forgive me as I am a beginner but if my bacteria was processing 2.0ppm of ammonia and nitrites were clear after 12 hours during my cycle, and since adding the first 7 fish ammonia and nitrite have been zero every day, would that not suggest that my bacteria is coping?
Livewire88, thanks for the info. I will keep a close eye on the remaining 5. I wasn't intending on adding any more fish for another 2-3 weeks so this will be a good bit of time to see how things progress. Either way, I won't add anymore Cardinals for a long time.
I appreciate your replies guys.
David

I know the topic has moved on now but unjust wanted to provide clarity on the b g able to fully stock after a fishless cycle.

In theory if you arendosin to 5ppm you are creating more ammonia than a fully stocked tank and therefore have sufficient bacteria to sustain a full stocking. However by adding the lemon tetra and nothing else you have reduced the bio load since the fishless cycle and some of the bacteria you had developed will have starved a died off. You can only keep sufficient bacteria alive to cope with the current bioload. From this point you need to stock slowly.

On top of this you should consider the fact that some species do not cope well in immature tanks even if cycled - many species are not recommended to be added to a tank less than 6 months old.

I wish you look with your tank

 
 
That's not exactly true.  The bacteria do not "die", instead they go dormant.  They can go back to processing bacteria fairly quickly if they are provided with ammonia again.  The speed with which they will process the ammonia again is highly dependent on the amount of time that they have been "starved".  Ultimately, the bacteria in this case have not been starved so long that they won't be able to process the ammonia again rapidly.

 

[David J]

Hi eagle,

I see. That also makes sense. I've heard a lot over the years about bacteria being dormant for ridiculous amounts of time as long as the conditions are right.

 

[eaglesaquarium]

I'll see if I can find a scientific article regarding this specifically.

 

[eaglesaquarium]

http/www.ncbi.nlm.nih.gov/pmc/articles/PMC126422/

After 1 to 10 weeks of ammonium deprivation, N. europaea became almost immediately active after the addition of fresh ammonium and converted the added ammonium within 48 to 96 h. In contrast, the regeneration time of the ammonia oxidizer G5-7 increased with increasing starvation time.

A quick search turned this up. The quote above was taken from the abstract. Obviously different species of the nitrifying bacteria respond differently, as this study shows, and we have no way of knowing which particular species are in your tank.

 

[David J]

Hi

That is interesting, and reassuring to know. Thanks for finding it. I'm glad this is the case because otherwise what is the point in going through all that work.

Thanks gain Eagle.

Avid

 

[daizeUK]

I've come to the conclusion that the best method is to fishless cycle while processing around 2ppm of ammonia, then stock gradually adding a few fish every couple of weeks.
 
The usual advice of 5ppm is to enable full stocking immediately, but personally I don't think that's a good idea (unless there would be territorial issues e.g. mbuna tanks).
 
But like Eagle says, your existing bacteria won't starve immediately, although they may take a few days to return to full strength when new bioload is added.

 

[eaglesaquarium]

I agree that the standard number of 5ppm is actually far higher than it really needs to be, and probably inhibits the process as much as it helps. 2-3ppm would be the spot that I'd aim and has been corroborated by Dr. Tim Havonec (one of the few folks who is actually studying the nitrogen cycle in an aquarium, rather than sewage treatment).  I believe that less is more when it comes to stocking, as well.  One of the most exciting parts of the process is getting new fish... so spreading that out is a lot of fun.  It helps to have a QT though, to avoid adding disease.
 
Ultimately, the biggest issue is that when adding additional fish, there is always risk.  I think the issue is that cardinals are sensitive to immature tanks, not just "uncycled" tanks.  I don't think its an issue of ammonia/nitrite as much as it is the entire biofilm of the tank that isn't established yet.  I've mentioned it before, but I'll mention it again... there is far more going on in the tank than what we are able to test for.  "Hardy" fish don't seem affected by these factors, while other fish that we term "sensitive" are best added to a tank that's been running for 6+ months.  I don't know why that's the magic time frame, but it seems to be the time based on empirical evidence.
 
There are other fish like cardinals that need more time for the tank to mature, neons, German Blue Rams, Discus, etc.  

 

[TwoTankAmin]

Have to disagree on the stocking,. One of the primary benefits of doing a fishless cycle is it allows for fully stocking at tank when it is completed. When it comes to bacteria dying vs going dormant it isn't quite so simple as it would seem.
 
The bacteria go dormant in response to a lack of ammonia/oxygen. When they sense the lack of these they basically react by going dormant. How long they can survive in a dormant state and how rapidly they may revive are dependent, to a great extend, on how well fed they were when things turned "bad." The better shape they were in, the longer they can last. And the longer more can last, the faster they can resume oxidizing and the more of them there will be to do so. Of course, how long they have been dormant will also be a big factor.
 
From what I understand, this would mean that when the food source is merely reduced rather than eliminated, the bacteria do not go dormant. Some will just die back from there not being enough food to go around and others will do just fine. Odd as it sounds, this would mean a too little food can sometimes do more harm to the colony than no food at all. I have to admit that this is supposition on my part and I am not sure if I am correct in this or completely off base entirely. If I am correct, this argues in favor of rapidly stocking upon completing a fishless cycle or one risks converting it back into a fish in cycle.
 
One last note. I have always found cardinal tetras to be flakey. They do not seem to like to travel, whether that is from SA to another country or the fish store to a home tank. I have found one thing that tends to improve the survival rate is to feed them live bbs for the first week to ten days.

 

[daizeUK]

Interesting.  If that's true, I might change my initial stocking plans.  Perhaps it is less advisable to fully stock all in one go for a first-time fishkeeper until we've wet our feet, though.

 

[David J]

Great I of twotankamin, thanks. One thing is for sure. When you start fish keeping, you learn a lot of stuff but not necessarily about fish as everyone would expect. I wonder now if I should add my next 2 spices n my list after my 2 week lock down is over. I was going to add 7 rasboras and then assuming all is well, a week or 2 later I was going to add 6 Panda Cory's. maybe I could add both of these at once as damage limitation to the colony?

So confused!

 

[Mikey1]

i would add 7, then wait another two weeks
 
adding 13 fish at one time is never really a good idea, unless the tank is huge and already has alot of fish in it (50+)

 

[David J]

Hi Mikey,

Yeh, thinking about it, it would make me nervous adding so many. It's just so difficult to know what to do for the best when you take into consideration the fish and the bacteria. A real mine field. Think I'll stick to the original plan of one species at a time.

 

[Mikey1]

Hi Mikey,

Yeh, thinking about it, it would make me nervous adding so many. It's just so difficult to know what to do for the best when you take into consideration the fish and the bacteria. A real mine field. Think I'll stick to the original plan of one species at a time.

 
 
fishkeeping is a constant learning process.....
 
i have been in the game for 25+ years, and i still learn new things pretty much everyday