What medications kills beneficial bacteria?

[new2betas]

Do either tetracycline or API's Triple Sulfa kill the beneficial bacteria in a tank? I am having to treat one of my female bettas who had a nipped fin from my 29g tank. I moved her to an empty, but fully cycled 5g tank to help her recover and noticed a couple of days later that she had some fuzz growing on nipped spot and it looked like she had maybe had a fight with the filter intake cover. I have been treating her with these medications and she is recovering, I think, but I wanted to know if these medications kill off the beneficial bacteria and I will have to cycle this tank all over again.....

 

[Purrbox]

Check the label, if it doesn't say that there's a risk of damage to the biological filter then contact the manufacturer for a more definitive answer.

 

[JohnPaul]

In general, I assume anything that is targeted at bacterial infections is going to be a heavy risk to your filter. I've seen from firsthand experience medications claiming they "won't harm your biological filter"....harming my biological filter and causing at least a mini-cycle.

This would be especially true of any medicine, or combo of meds, said to be effective against both gram-positive and gram-negative bacteria. Because the filter bacteria are all either one or the other, and if you're putting in medicine that can kill both, then I guarantee you that you are killing your bacteria.

 

[Innovator]

Virtually all medications negatively disrupt your biological filtration. Probably not cause all the bacteria to perish, but negatively impact it.

 

[new2betas]

Well I guess according to what you are saying JohnPaul, I have probably killed it as it does say for gram negative and positive. But, she was in such bad need of medicine, simple water changes weren't gonna do it for her. But, fortunately, I have enough filter media in my house with my other tanks that cycling shouldn't be a problem.

 

[JohnPaul]

For the future, if you are medicating a tank it is best to disconnect the filter while the medicine is in the water and put the media from it in another tank so that the bacteria will remain alive. And then just rely upon PWC's to keep ammonia levels under control. (Of course, too much water changing also takes the medication out of the water, which you don't want to do, so it's always a catch-22).

 

[new2betas]

For the future, if you are medicating a tank it is best to disconnect the filter while the medicine is in the water and put the media from it in another tank so that the bacteria will remain alive. And then just rely upon PWC's to keep ammonia levels under control. (Of course, too much water changing also takes the medication out of the water, which you don't want to do, so it's always a catch-22).

I did take out the biowheel from this filter and kept it in another tank for the time being. But it does have a sponge filter in there. I was just concerned about the bacteria on it and the gravel, etc. I figured I was killing it and was preparing myself for having a small cycle once medication is completed. Thanks for your advice. It is definitely a catch-22!

 

[Jnam]

I just got done treating some finrot with Tea tree oil. Basicly detroyed the 2.5gallons biofilter had to recycle the qt tank after the treatment the molly survived and is doing well.

 

[bluerose]

TTO is a pretty hefty antibacterial agent so yup... bye-bye biofilter.

I agree with JohnPaul's posts, see no need to say it again!