Setting up new used tank question

[123]

What happens if I take the filter off of my old (currently already cycled tank) and put it on my new tank? Will it shorten/aleviate the cycle? If I do that, can I immediately move fish from old tank into new tank? Or do I still need to wait for it to cycle?

 

[Lotus]

It will significantly shorten the cycle if you put the filter from the old tank on the new tank. If you're not moving all the gravel and decorations, there will be some cycle.

If you're planning to stock your old tank, you'll need to remember that some of the bacteria have been moved, so you would need to take it slowly with stocking.

 

[Seleya]

What exactly are you planning to do? If you're breaking down the old tank, the more you move over, the better. How many and what types of fish are you moving? What's staying in the old tank? Anything you move to a new tank from an established tank will help with cycling (how long has the original tank been set up?) -- filters are one of the main areas where the biofilter is - gravel being the other, secondary one.