From what I understand Atta queens take a tiny piece of fungus from the colony they came from. I don't know if they hold onto it until the eggs develop or they begin cultivating it immediately. Either way the piece of fungus will be very very small, maybe too small to notice.
As dudamota, uta and me already said, the queen takes some fungus with it.
Then she splits it out and it grows rapidly, please first read the thread before answering.
The main problem with that gel is that it is highly unnatural, would you like to live in something like that?
Also the stuff it is made off isn´t good for keeping ants, it is to whacht them die and is called "observation" by the maker.
I can not imagine rising a colony in that.
When it is to dry it shrinkes and that is not good and when it is too wet it also changes it form, what is fatal for the ants living in that.
It has nothing to do with sand and ants just don´t want to found in something like that.
as I said before :
I've created one of these before and she began to establish the fungus in about two days.
In the beginning I thought eggs were huge but looking closely I saw that they were not eggs.
I started researching and saw that it was the fungus growing.
But now after 2 weeks she just lays eggs and do not see the fungus growing.
and eggs that she puts in time disappear.
I am seriously considering the chance to dig and search the fungus.