Depends on how fast they cycle.
Taking water from an established tank will not do you much good because your nitrosomonas and nitrobacter bacteria are not free floating. These stick to surfaces of rocks, filter media, substrate and so forth. Anything that you can tank out of your established tank will help you in this case. So for example you put filter media from your tank into this new tank it should speed up the cycle time to pretty much a day or so.