Preparing myself for a fishless cycle

[Fishy123]

Hey there everyone! As some of you know, I bought my first tank yesterday, a 40 gal breeder. Still looking for a stand, so nothing is set up yet, but I have been reading about fishless cycling for a while now, and following some different threads on this forum as members go through the process.

I have a pretty good grasp on it, but one thing kind of confuses me. I get that you add the ammonia in a level that would be leathal to fish in order to build up the bacteria to a level that can handle that much ammonia. Once the colony is built up to handle such a load, you need to keep feeding it so it doesn't die off until you add fish.

My question comes in with the adding fish part. If I cycled my tank, and have a colony of bacteria able to chow down 5ppm ammonia in less than 24 hrs, then I add let's say 7-8 zebra danios into the tank, will they create enough bioload to keep that colony of bacteria alive or will I loose most of it?

I guess I'm concerned that when I add the second group of fish it will be an overload and ammonia will spike harming the fish because the colony I created didn't have enough "food" to sustain with only a few fish. Should I add more fish at once? I seem to find conflicting reports on this part.

 

[CoyoteWildfire]

Unfortunately, conflicting opinions will always make this part of the cycling process difficult. A lot of people recommend you only do two or three fish at a time. This way you can isolate any problems, or any sick fish and quarantine them. Also, it helps establish a "pecking order" which may reduce aggression in some species, as not all the fish will be jockeying top dog.

And then there's the side that has the concerns you do.

Overall, I suppose it comes down to what type of fish will be in the second group you're adding to your tank? And how many? The bioload of the fish will determine the impact it will have on your biological filter.

Yes, I think you'll be fine adding all those Danios, but bear in mind that you're never going to be able to match your bio load to your exact bacterial colony. Any excess bacteria will die off, or it will grow to meet your bioload if too small.

So long as you continue to monitor your parameters and do regular water changes, the worst I would say could happen is a mini-cycle. I wouldn't be too worried about your colony dying off as if you add fish gradually after your Danios, the ammonia spike won't be too drastic. And as long as you're doing your ammonia tests, you'll know exactly when to change the water.

Yes, it's true that no ammonia is the sign of a cycled tank, and that higher ammonia isn't great for fish, but this is also going to be something you run into every time you add new creatures to your tank. The question just becomes how much of an impact is it going to have? And that will determine how many you should add or how long it should be before you add new fish.

 

[Homedog98]

Unfortunately, conflicting opinions will always make this part of the cycling process difficult. A lot of people recommend you only do two or three fish at a time. This way you can isolate any problems, or any sick fish and quarantine them. Also, it helps establish a "pecking order" which may reduce aggression in some species, as not all the fish will be jockeying top dog.

And then there's the side that has the concerns you do.

Overall, I suppose it comes down to what type of fish will be in the second group you're adding to your tank? And how many? The bioload of the fish will determine the impact it will have on your biological filter.

Yes, I think you'll be fine adding all those Danios, but bear in mind that you're never going to be able to match your bio load to your exact bacterial colony. Any excess bacteria will die off, or it will grow to meet your bioload if too small.

So long as you continue to monitor your parameters and do regular water changes, the worst I would say could happen is a mini-cycle. I wouldn't be too worried about your colony dying off as if you add fish gradually after your Danios, the ammonia spike won't be too drastic. And as long as you're doing your ammonia tests, you'll know exactly when to change the water.

Yes, it's true that no ammonia is the sign of a cycled tank, and that higher ammonia isn't great for fish, but this is also going to be something you run into every time you add new creatures to your tank. The question just becomes how much of an impact is it going to have? And that will determine how many you should add or how long it should be before you add new fish.

+1

 

[eco23]

I just posted this on another thread, so instead of retyping, I'll just copy and paste

Also, a note about stocking... There's still some debate on this. Most articles say a tank cycled to handle 4ppm in 24 hours is ready to handle a full bio load of fish. Other people still say to add a few of them every other week. I tend to agree with the first argument, but I went with the middle ground. 4ppm is serious overkill and there is absolutely no way a fully stocked aquarium will put out that much waste in 24 hrs. On the other side, I believe that if you only throw 5 tetras into a newly cycled tank, theyre not going to put out enough waste and I worried about a bacteria die off since they aren't getting enough food.

I stocked my tank to around 50% capacity at first and my numbers haven't budged. So I'm actually heading out this weekend to pick up a few more. So, probably not a good idea to go to either extreme...just get a reasonable sized group of fish to put in at first. Good luck!

 

[Fishy123]

Thanks for the replys, and eco23, it's nice to know I'm not the only one who thought that way. Makes me think at least maybe I might be grasping this stuff! Now if I could only find a stand to put my tank on I could get started on this whole process!

 

[BigJim]

I prefer to be conservative when stocking after a fishless cycle. Even if the biofilter is capable of handling a full stocking, other problems can arise when you add too many fish at the same time. I'd rather lose a few bacteria to starvation than lose fish to stress, illness, etc.

 

[Mr. Limpet]

I prefer to be conservative when stocking after a fishless cycle. Even if the biofilter is capable of handling a full stocking, other problems can arise when you add too many fish at the same time. I'd rather lose a few bacteria to starvation than lose fish to stress, illness, etc.

+1

I prefer to choose my heartiest fish first, let the bacteria adjust to the bio load, then 3 or so days later start adding another shoal and so on. Better to lose/deal with a few fish than a full tank of them.

 

[eco23]

I agree to a point. But if you have a 55 gallon tank that you add 3 neon tetras to, and wait 3 week to add more fish... You are in a way invalidating the purpose of a fishless cycle. 4ppm is the standard ammo load for a fishless cycle and is serious overkill, that being said your tank is prepared to handle the maximum number of fish that does not expose them to other stresses like incompatibility and overstocking. There is a reason that the actual SCIENTISTS that created the method of fishless cycling concluded that 4ppm of ammo is a suitable level. If the purpose was to add 3 neon tetras at the onset, why not train the tank to handle .25ppm of ammonia instead of 4ppm? As long as the number of fish added does not cause additional problems such as lack of time to establish territory or pecking order, or prevent illness, what is the point of establishing such a substantial bio-filter if your first action is to kill off 80% of the bacteria? This is not simply opinion...this is scientific fact presented by scientists such as AA member 7enigma (an actual scientist) who presents the process of fishless cycling in it's purest form?

 

[eco23]

Also if you reread my previous post, I recommend a middle ground approach to the argument. I have no doubt that both camps have reasons based in truth, but IMO you have to consider the actual process and the principle of the fishless cycle.

 

[Mr. Limpet]

I agree to a point. But if you have a 55 gallon tank that you add 3 neon tetras to, and wait 3 week to add more fish... You are in a way invalidating the purpose of a fishless cycle. 4ppm is the standard ammo load for a fishless cycle and is serious overkill, that being said your tank is prepared to handle the maximum number of fish that does not expose them to other stresses like incompatibility and overstocking. There is a reason that the actual SCIENTISTS that created the method of fishless cycling concluded that 4ppm of ammo is a suitable level. If the purpose was to add 3 neon tetras at the onset, why not train the tank to handle .25ppm of ammonia instead of 4ppm? As long as the number of fish added does not cause additional problems such as lack of time to establish territory or pecking order, what is the point of establishing such a substantial bio-filter if your first action is to kill off 80% of the bacteria. This is not simply opinion...this is scientific fact presented by scientists such as AA member 7enigma (an actual scientist) who presents the process of fishless cycling in it's purest form?

Actually I said 3 days, not 3 weeks and a shoal of tetras should be a minimum of 6 or 7, in a 55g 9+ would be called for IMO. Althought I wouldn't pick tetras as a first fish because they tend to be a bit on the soft side when it comes to acclimating to a tank, much less a freshly cycled one. I based my suggestion on countless research I've done when setting up a new tank.

 

[eco23]

Actually I said 3 days, not 3 weeks and a shoal of tetras should be a minimum of 6 or 7, in a 55g 9+ would be called for IMO. Althought I wouldn't pick tetras as a first fish because they tend to be a bit on the soft side when it comes to acclimating to a tank, much less a freshly cycled one. I based my suggestion on countless research I've done when setting up a new tank.

Consider the term "3 weeks" as a metaphor of the point I'm making. The reason I am making this argument is due to the fact that the vast majority of people who ask this question and join AA to research this topic are inexperienced hobbyists who when told to stock only a few fish every couple weeks do not understand the required number of fish that defines a school, or even fully understand the requirements of sustaining a bio-filter. I am not speaking personally to your post of every few days, but I have seen numerous posts of advice to add fish at a pace of a couple at a time over a course of weeks. Again, there is a middle ground and that is what I believe people should strive for. One where fish are not stressed or exposed to potential illness, but one that does not invalidate the purpose of a fishless cycle at the degree it is performed at.

 

[Mr. Limpet]

Consider the term "3 weeks" as a metaphor of the point I'm making. The reason I am making this argument is due to the fact that the vast majority of people who ask this question and join AA to research this topic are inexperienced hobbyists who when told to stock only a few fish every couple weeks do not understand the required number of fish that defines a school, or even fully understand the requirements of sustaining a bio-filter. I am not speaking personally to your post of every few days, but I have seen numerous posts of advice to add fish at a pace of a couple at a time over a course of weeks. Again, there is a middle ground and that is what I believe people should strive for. One where fish are not stressed or exposed to potential illness, but one that does not invalidate the purpose of a fishless cycle at the degree it is performed at.

I agree that it can be taken too far on either extreme, but I also feel that putting 20 or 30+ fish (other end of the extreme) in all at once is a disaster waiting to happen.

 

[eco23]

I agree that it can be taken too far on either extreme, but I also feel that putting 20 or 30+ fish (other end of the extreme) in all at once is a disaster waiting to happen.

I absolutely agree with the point of avoiding the extreme, whether it be over or under stocking. For example, when I initially stocked my 48 gallon I added a small school of neons, red eyes and danios. All peaceful community fish that are all happy, healthy and my parameters have not budged one iota. It all comes down to experience and knowledge of species of fish and how they will acclimate to their new home. That lack of knowledge of most new members is exactly why i would promote the average hobbyist to strive for a middle ground.

 

[BigJim]

There's a difference between being conservative and ridiculously overcautious. Adding five neons to a fishlessly cycled 55g is a joke, however, adding five neons to a fishlessly cycled 10g is significant. It all depends on the size of your tank.

4ppm is the number tossed around here on AA. I've read articles recommending anywhere from 1ppm to 5ppm. Your local water chemistry can change your ideal ammonia concentration.

 

[eco23]

With all due respect (and I honestly believe we're all on the same page, just different wording), I stand by my initial post that as long as the number of fish is at a reasonable level for your particular situation, and does not cause stress or confrontation with your first additions, a middle ground should be the goal. Most new members do not understand the complexities of the situation and to put it into simple terms, should be told not too many, not too few.

 

[Fishy123]

Okay, I feel better knowing this is contoversial in the hobby, and that I wasn't just missing something somewhere that made it all make sense. I agree with eco23's position of taking the middle road. I guess I wanted to make sure adding more than 4 or 5 fish would be ok, and he is proof of that it is. I can say as a new person to the hobby, the internet is the only place I hear about fishless cycling. Local people I know who are in the hobby, and lfs all gave me the run down on how to cycle with fish....So it can be very confusing sorting through the info, and knowing what the best thing to do is.

 

[eco23]

Okay, I feel better knowing this is contoversial in the hobby, and that I wasn't just missing something somewhere that made it all make sense. I agree with eco23's position of taking the middle road. I guess I wanted to make sure adding more than 4 or 5 fish would be ok, and he is proof of that it is. I can say as a new person to the hobby, the internet is the only place I hear about fishless cycling. Local people I know who are in the hobby, and lfs all gave me the run down on how to cycle with fish....So it can be very confusing sorting through the info, and knowing what the best thing to do is.

You'll always get differing views on virtually every topic. In fact, if everybody agreed on everything all the time, it would prevent the hobby from growing and developing better ways to care for fish. The way I approach things is to get as many different opinions as possible, and if there is an overwhelming majority of people who have experience and personal results, that is the direction I go. However if there are 2 conflicting views, the answer is usually somewhere in-between. We do all agree that being cautious is the correct way to go because you don't want to jeopardize all the work you put into fishless cycling by recklessly adding an overload of fish. But just like you said, if you have a 40 gallon tank and had been told to only add 4 small fish initially, that would be the other end of the spectrum and can potentially cause problems on that side as well.

You're absolutely doing the right thing by asking for opinions though. Good luck with your fishless cycle, and feel free to ask any questions along the way!

 

[eco23]

Also as a side note, personal responsibility and common sense plays a huge role here. IMO, adding 10-12 danios or tetras is one thing...adding 4-5 giant Oscars or Pleco's is a whole different ballgame. It's obviously not just the actual number, it's the bioload the fish will place on the tank that matters. I'm sure you know this, but it never hurts to add a disclaimer