Quick Filter Question

[kiriyama]

Hi, I have a small internal filter set up in a new small tank, I took media from an oversized external which was on my main tank. I filled the internal 100% (initially 50%) it has ran in the small tank for about a week now. "Borrowed" 3 Danios for cycle, I stripped the tank down after rehoming fishes (didn't like the sand, very muddy colour), anyways I put the small internal into the main tank with the oversized external. If it stays in the main tank for about a week will this help cycle it as well ?
Not sure which section this was supposed to go into
Any correspondence greatly appreciated

 

[Honeythorn]

As long as the main tank is stocked with fish or you are feeding it with ammonia then yes.

If you filled it with dirty media fully then it should already be fully cycled. Since you have basically filled it to the brim, from the beginning with bacteria laden media already grown and able to take a full load of fish waste.

If you want to make doubly sure that it's fully cycled and ready to go then leave it in your main tank for a couple of weeks anyway while you sort out the other tank.

 

[kiriyama]

cheers, better safe than sorry, for something so relaxing you can't help but worry