How do I change a filter without killing all of my BB

So I just got a new filter because my old one has a hole in the back so not all of the water was getting clean. Now that I have a new one how do I keep my cycle from crashing?

 

Here's the type of filter if it helps. It says it has scrubbers to help remove ammonia and nitrites. Does that mean I can just transfer the aragonite from the old filter and put that one strait in. Also I have new fish that I will be putting in once they get properly acclimated. Does that make a difference?

 

I'm not familiar with those bio scrubbers but you would just transfer your old filter media into your new filter so that you don't lose your cycle.

 

Ok. I got to looking and the cartridge for the new one doesn't open. Would it be safe to put the old filter media in my substrate or should I try to drop some in the bottom of the new filter?

 

It's best to put the old media next to the new cartridge so it seeds it. It would also be better for the bacteria to be where the water flows as well which is why you want to keep it in the filter. You mentioned aragonite but what else do you have in the old filter in terms of media? Was there a cartridge? If so, you could cut the floss surrounding it and stuff that next to the new cartridge.

 

It was a bio bag that had carbon and aragonite/crushed coral in it.

 

I'd discard the carbon but try to fit in the aragonite, coral and the material around it.

 

Ok. And can I go ahead and put it in even though I'm going to be adding fish later tonight?

 

Is this your 10 gallon with the 3 danios? What else were you planning to add?

Just want to mention that danios are schooling fish that need at least 6+ of their own species and really are only suitable in a 20 gallon min.

 

Sorry for how long it took me to answer. I know it's supposed to be 6+ in a 20 gallon or more but my grandmother brought them to me from Savannah without my prior knowledge and my LFS won't take them because they weren't bought there and even if they had been the purchase was over 3 days ago. ( she kept of them in that little bag with less that half just over a quart of water for 3 days without feeding them.) So now I have 5 danios in a 10 gallon.

 

Well, hopefully you can upgrade soon. I wouldn't add any more fish into this tank though.

I'd go ahead and make the transfer of the old media to the new filter if you haven't already done so.

 

I transferred the media. My mom said if I made all A's and had a job by November then she might get me a bigger tank for Christmas.