Started cycling a new tank.

Hi,

I was put in charge at work of moving the three goldfish into a new
bigger tank.

The poor guys have been living in a cramped 5gal tank and it was about
time to do something about it.

We got a 20Gal tank and I just set it up today.
I used city water and to condition it I used aqua-plus from Hagen and
plan on leaving it running until monday, so the water warms up to room
temperature, when I plan on moving one goldfish into the tank to start
the cycle.

In the old tank I added another sponge to the filter a couple months
back to help filtering and I plan on using it on the new tank to help
with the bacteria growth.

My question is about timing.

When should I move the sponge?

Before the goldfish, How far ahead?
At the same time?
After? How long after?

Obviously once the fish is in there I will keep an eye on the water
quality and put up with water changes.

Anything else I should be doing?

thx.