I don't come to the google translator so is plaster the same as Gips in german?
If it is: they come better through it, then through Ytong, and a big colony don't need days for tunneling in plasterparts of a nest- in the arena I used it too, but they dont try to destroy... perhaps because I just give water to it sometimes and not often!?
Through Ytong they tunnel very fast and you may see just a small amount of the colony, hundrets of ants could be there and you would not see them, often the queen is with them and you may think that she is dead... not very good for the ant-holder, and they could escape this way too!
Experiences with stronger building materials are made here:
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