Filtering My Tetra Whisper3I In My 30 Gal

[Hmongol]

I have a 3.5 gallon tank that I haven't used for awhile but now would like to use it for a betta. My question is, can I install the small whisper 3i gallon filter in my 30 gallon so it can build up beneficial bacteria. I don't want to do a fish or a fish-less cycle for my betta tank, so can I just install the small filter in my 30 gallon to accumulate bacteria over 2 week or 3 than put it into my 3 gallon?

I'm afraid that when I take out the small filter back into it's 3 gallon, that the water won't have ammonia for the bacterial since it will be a brand new tank and water with a betta thrown in right away?

Thanks in advance!

 

[Miss.Ward]

starting up with my new tank i put my smaller filter in my big tank to build up then put water from my running tank to my smaller tank

 

[Hmongol]

nice, i didnt even think about that

 

[Joshwainwright]

That sounds alright to me, I'd look out for any ammonia spikes though even though it's just the one fish. It's always better to be safe