If i were to take a fully mature filter from one tank, and transfer it to a new and uncycled tank. is this cloning?
Yes, it is cloning. Once you add it to another tank, it's completely able to remove the same amount of waste from fish in the second tank as it did in the first one. The word "cloning" is usually used to mean taking part of the filter media from one tank and starting up another. In that case, half the media would support half the amount of fish, etc.
For example, last week I came home from the lfs with four fish I had not expected to buy, and needed to set up a quarantine tank for them immediately. Since I use box filters, it was easy enough to pinch a bit of filter floss from the filters in several different tanks I have running, and replace it with new floss. The beneficial bacteria will soon reproduce and rebuild its numbers in the old filters, and the bacteria I moved to the new filter will continue doing its job in the tank I just set up. The new tank is a cloned tank.
Dorsey mentioned "maturity," which is something else again. Some of the more delicate fish have additional requirements that go along with a longer running tank, but others do not. Otos, for example, should only be added to a tank that has growing plants and algae.
Almost all beneficial bacteria will be found clinging to the surfaces of the tank. Most are in the filter media, and some are in the first 1/2" to 1" of gravel, where there is more water circulation than the deeper gravel gets. Some will be found on the glass, decorations and plants too, but very little is free floating in the water. When you set up a second filter, once some get into it, they will begin to reproduce and the eventually the total number will be divided between the two filters. How long it takes is probably dependent on the rate of water flow, etc.
As dorsey also mentioned, it is very important to add more fish to a new tank with live bacteria in it to keep the bacteria from starving and dying off.
I like to fill a new tank 1/4 to 1/3 of the way with water from another tank. It seems to keep the formation of bubbles to a minimum and generally get things off to a good start, but this has nothing to do with the beneficial bacteria.
