Cycling a new filter for an established tank

[illumnae]

I've just bought a new filter for an established tank. How should I go about cycling this filter to establish beneficial bacteria in the media? From what I understand, the 4-6 week cycling process is for bacteria to actually form in the tank and multiply. So if I were to put the filter media meant for this filter into an already established filter (not the same tank I intend to use this filter on), how long would I have to put it there for before it's considered "safe" to replace the old filter (assuming I will also take the biomedia of the old filter and put it into the new one)? Would it still be 4-6 weeks, or would a few days suffice, since bacteria multiplies fast

[Quixotic]

I am not sure that nitrifying bacteria will multiple that fast. Although I am unable to verify the validity of the following figure, what is written in the entire article seems pretty sound to me.
http://www.faqs.org/faqs/aquaria/general-faq/beginner/ (section on Beginner FAQ: The Nitrogen Cycle, and "New Tank Syndrome")

In comparison to other types of bacteria, nitrifying bacteria grow slowly. Under optimal conditions, it takes fully 15 hours for a colony to double in size!

This is also with reference to the ammonia/nitrite conversion chart, http://www.aquaticquotient.com/forum...94&postcount=2, so it can be rather slow for the nitrifying bacterias to colonise the surface area.

However, since you are going to use the biomedia in the old filter to seed your new filter, I don't think it will be a big issue, unless the bioload is really high, which upon cycling for a week will probably be safe.

[illumnae]

Some more info about my setups, hopefully it can give a clearer picture

i currently have a 25 cm cube nano tank that is cycled and using a HOB filter (using 2-3 sticks of biohome as filter media). I also have another 2x1x1 ft apisto tank with a large HOB that's cycled and has space in its filter cavity to hold more media.

I bought a Boyu mini-canister for the 25 cm cube, and am thinking of taking the ceramic rings that come with the canister and putting it in my 2x1x1 filter to accumulate beneficial bacteria, before returning it to the canister and hotswapping the current small HOB with the canister. I will also be taking the 2-3 sticks of Biohome from the small HOB and putting it into the mini canister.

with this situation, would a couple of days in the big 2x2x1's HOB be sufficient to seed the ceramic rings?

[Quixotic]

IMHO, a couple of days isn't good enough, I would suggest up to a week.

But why so troublesome? You can run the Boyu filter concurrently with the HOB in the 25 cm tank. After a week, just remove the HOB and move the Biohome into the Boyu filter.

Hmm... if you are thinking that the bacteria will colonise faster in the 2x1x1 ft tank compared to the 25 cm tank, then I don't think it will make a difference.

[illumnae]

haha it's not because the bacteria will colonise faster in the 2x1x1, but because my 25 cm cube can't afford the extra flow =) it houses bettas which prefer still water as it is, if i were to have both filters running concurrently, it'd be a whirlpool in there!