Cycling tank with half old and half new water?

HI everyone. I just have some questions I wanted to ask u guys about starting a new tank. I hope this is not a silly question but here I go. Ok so I was just thinking about this idea for starting a new tank with 50% established tank water from let's say another established tank and 50% new water like what u would do in a normal water change. How would that go? Would it be safe? Would I have to check the water parameters to see if it was fine or what? Would it still have to go through the nitrogen cycle? Or would it just shorten it? I'm just tampering with this idea. I think that's all the questions I have on this idea. Any input is appreciated

 

Tank water holds very little beneficial bacteria. So adding water old tank water to a new tank will not jumpstart the nitrogen cycle. Taking filter media from an established tank will jump start your new tank. I would still use bottled ammonia and test the water for a week to see how the BB are processing it and if they're ready to handle the fish bioload.

 

Oh so adding established tank water doesn't do much. Thanks for ur input

 

As qchris87 mentioned, it's all about the filter. I often read on how to "cycle a tank" and it can be misleading to some newbies and I can understand but what you need to be concerned about is cycling and maintaining the filter.

 

Oh ok. Ya I just thought that the established water could be helpful and yes I know the filter houses beneficial bacteria

 

The only reason you might want to use water is if you're exchanging fish from one tank to the new tank, to keep parameters comfortably similar.

As far as beneficial bacteria goes, the water won't hold much of it, it's strongest in the filter media.

 

Hmmm that is a good idea since I will be moving my cichlids around soonthanks for the info