Upgrading/Cycling Question

[Ceiora]

I want to upgrade my 2nd 2.5 gallon (as I’m currently in the process of upgrading the 1st) to double the size with a 5 gallon.

My question is, can I get away without cycling the new tank if I take everything (substrate, decor, equipment, water) and put into new tank? Would it not be the near equivalent of doing a 50% water change?

Second question: if I want to change filter to a sponge filter instead of the stupid cartridge one after moving to new tank, can I just hook up the sponge and leave the old cartridge in for a bit or safe to remove completely and replace?

Edited November 1, 2020 by Ceiora

[Daniel]

Just now, Ceiora said:

I want to upgrade my 2nd 2.5 gallon (as I’m currently in the process of upgrading the 1st) to double the size with a 5 gallon.

My question is, can I get away without cycling the new tank if I take everything (substrate, decor, equipment, water) and put into new tank? Would it not be the near equivalent of doing a 50% water change?

Second question: if I want to change filter to a sponge filter instead of the stupid cartridge one after moving to new tank, can I just hook up the sponge and leave the old cartridge in for a bit or safe to remove completely and replace?

That is what I would do. I think your analogy of 50% water change is correct.

[Larrimore]

You could throw a sponge filter into the old tank for a few days before making the change.  If you did that, I wouldn’t worry about the old cartridge.  

[Ceiora]

I couldn’t resist, I did it. The original tank was just too small, especially for such a crazy active betta. And tonight was the one night that I didn’t have a 3 year old all over me lol.

Before:

After:

[RovingGinger]

With one fish you’re probably safe just completely swapping filters but to stay extra safe I’d let both run for a week. Great job on the transplant.