Betta separated - now what?

[VioletThePurple]

My betta in a community tank killed a fish when I came home from vacation. So now she's in a quarantine tank, and I'm going to have to get another tank for her permanent home. I already know about the basics, but my biggest question is, will I need to cycle the tank? I already have a 20 gallon so I could fill up a five gallon completely with the normal amount of water I take out for water changes in the 20 gallon. I'm hoping I won't have to cycle, because the quarantine tank is quite small and I don't know if I can keep her alive in there for the months it takes to cycle.

 

[HoldenOn]

Take a small amount of filter media out of the 20 gallon and put it into the filter of the new tank. This will place an established colony of beneficial bacteria into the tank. From that point monitor parameters, especially ammonia, very closely. Some daily water changes may be needed at the very start, but placing a little bit of filter stuffs from the 20G into the new tank will speed things up very nicely. That being said, if the 20G is the same one with the sickness problems, I would wait till you've let the treatment run it's course.

 

[VioletThePurple]

Take a small amount of filter media out of the 20 gallon and put it into the filter of the new tank. This will place an established colony of beneficial bacteria into the tank. From that point monitor parameters, especially ammonia, very closely. Some daily water changes may be needed at the very start, but placing a little bit of filter stuffs from the 20G into the new tank will speed things up very nicely. That being said, if the 20G is the same one with the sickness problems, I would wait till you've let the treatment run it's course.

Of course it's the same one, it's my only main tank. Unfortunately I don't know what's wrong in it.

 

[Byron]

Until you sort out the issue that is killing the cories, it is best not to move any water or wet items (filters, plants, substrate, decor) to a new tank, just in case.

As for cycling the betta's new tank, you have some options. Assuming this is a five gallon, one betta is not going to have issues anyway, especially if you can put some floating plants in the tank. These benefit bettas but they also will easily assimilate any ammonia from one betta.