Stocking After Cycle Question

[starlitsunrise]

Hi guys,
 
As some of you may know I have a 10 gallon tank that just finished fish less cycling on the weekend and is currently the home of my betta.
 
I am planning on getting 6-8 pygmy cories for the tank as well but I am not sure when. The local fish store said they would be getting some in sometime next week but I will be out of town until the 30th. 
 
So I guess my question is will only having my betta in the tank mess with the good bacteria from the cycle? And if so, how should I go about adding the cories after I get back? 
 
Thanks for your help!
 
 

 

[TallTree01]

Well, when the bacteria are without ammonia for too long, they will die.
Your betta will produce less ammonia than a betta and 9 Pygmy cories, so when you add them, you should expect an ammonia spike.
You have one or two options really, add them at once, and do waterchanges to dilute the excess ammonia with new fresh water, you can add 1-2 cories at a time so the spike is not as dangerous.

 

[starlitsunrise]

 

Well, when the bacteria are without ammonia for too long, they will die.
Your betta will produce less ammonia than a betta and 9 Pygmy cories, so when you add them, you should expect an ammonia spike.
You have one or two options really, add them at once, and do waterchanges to dilute the excess ammonia with new fresh water, you can add 1-2 cories at a time so the spike is not as dangerous.

 

Ok, so as long as I monitor the ammonia levels carefully and change the water accordingly I should be fine with either option, correct? 

 

[TwoTankAmin]

I just checked on your tank in earlier post and see you have plants. If you fully cycled the tank and then put in the betta you cycled to a greater level of bacteria than the lone betta would need. Since the tank does have an ammonia source, some of the bacteria will make it. What happens is because there is less ammonia than can feed the number of bacteria you developed, there is no excess ammonia which means reduced or no reproduction. So as the bacteria than normally die and get replaced will not be replaced. But this takes some time and not all of them will be gone.
 
But the plants in the tank also will use ammonia. So between those plants and bacteria still in the tank you should be able to add the cories in several additions. if the betta is a decent sized one the odds are decent that you can 4 and then make sure over the week thereafter you have no cycling issues. If you get low levels of ammonia, .5 ppm or lower, the fish can likely ride it out for the short time it will be there.
 
Once you are sure the tank is working fine with the betta and the 4 added cories, you can go ahead and add the last 5. basically this process is designed to control the increase in the bioload in any one go. Pygmies are small fish and this should work. If you really want to be a tad safer then add them 3 at a time. As a general rule you can estimate the increase in bioload based on the body mass of the fish involved. What you are doing is trying to hold down the amount of the mass going in to about 25-30% of what is in place. In your case the plants make it possible potentially to be more in the 35-40% range.
 
In terms of the bacteria the more you start with, the faster they can cover a reasonable increased bioload. Think of when you cycled your tank how long it took for the first ppm or two of your first ammonia addition to drop compared to the next few times you added that amount of ammonia.

 

[starlitsunrise]

I just checked on your tank in earlier post and see you have plants. If you fully cycled the tank and then put in the betta you cycled to a greater level of bacteria than the lone betta would need. Since the tank does have an ammonia source, some of the bacteria will make it. What happens is because there is less ammonia than can feed the number of bacteria you developed, there is no excess ammonia which means reduced or no reproduction. So as the bacteria than normally die and get replaced will not be replaced. But this takes some time and not all of them will be gone.
 
But the plants in the tank also will use ammonia. So between those plants and bacteria still in the tank you should be able to add the cories in several additions. if the betta is a decent sized one the odds are decent that you can 4 and then make sure over the week thereafter you have no cycling issues. If you get low levels of ammonia, .5 ppm or lower, the fish can likely ride it out for the short time it will be there.
 
Once you are sure the tank is working fine with the betta and the 4 added cories, you can go ahead and add the last 5. basically this process is designed to control the increase in the bioload in any one go. Pygmies are small fish and this should work. If you really want to be a tad safer then add them 3 at a time. As a general rule you can estimate the increase in bioload based on the body mass of the fish involved. What you are doing is trying to hold down the amount of the mass going in to about 25-30% of what is in place. In your case the plants make it possible potentially to be more in the 35-40% range.
 
In terms of the bacteria the more you start with, the faster they can cover a reasonable increased bioload. Think of when you cycled your tank how long it took for the first ppm or two of your first ammonia addition to drop compared to the next few times you added that amount of ammonia.

 
Thank you for all of that information It is very helpful!