fish cycle or fishless cycle

Water from a live tank will do very little if anything to help you,filter media will help a lot, as will gravel from the top 1/4"- 1/2" of the estabilished tank.

Fishy cycles are difficult to do without harming fish. They can be done but they are a lot of work, with a lot of risk.

Fishless are relatively easy by comparison, and will prepare your tank for a full bio-load all at once, so they really are far superior in my opinion.

Either way you go, transferring media or gravel from your estabilished tank will speed things up drastically, and time frames will be about the same with fishless or fishy either one.
Dave

I have successfully instantly cycled 2 tanks ( a large and a small ) by using filter media from an established cycled tank. The best thing to do would be to let your filter for the new tank run on your old tank for at least a couple of weeks, probably longer

Bencareful about using a filter media or substrate from another tank to seed your new tank since can also introduce unwanted pathogenes already existing in your older tank.

There number of hardy fishes that can withstand the cycling process of a new tank. Choice is your ... there in right or wrong choice.

The water contain no bacteria since bacteria need a surface to colonize. Using water from an older tank will do absolutely nothing to seed a new tank.

Rohn

Bencareful about using a filter media or substrate from another tank to seed your new tank since can also introduce unwanted pathogenes already existing in your older tank.

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While I fully agree with the basis of this thought, I generally am not scared of my own tanks. If they contain pathogens of a negative type I will kill them. If you don't have problems with your existing tank, then you should be fine.

This warning definately applies to media from an unknown tank. I do not add things from other peoples tanks, even those whom I trust greatly.
Dave