Using water from betta for new tank

I’m wondering if I can use cycled water from my betta’s tank (when doing a water change) to kick-start the cycle of my new 10 gallon?

 

The water in your existing tank won’t do much, if anything, to kickstart a cycle, but using some filter media from your existing tank will be a better option.

 

The majority of beneficial bacteria do not live/float around in the water column which is why it won't kickstart your new tank. It's best to use established media to kickstart a new cycle.

 

I’m wondering if I can use cycled water from my betta’s tank (when doing a water change) to kick-start the cycle of my new 10 gallon?

It may introduce enough nitrifiers into your new tank to get a cycle going, but that really is a bit of a luck of the draw kinda scenario.

 

If there is a filter in your betta tank? If so you could squeeze it out in your new tank.