Cleaning out the cage (can be as simple as spraying it out with water to wash out all ants), then relocate to a different area is all you need to do as a minimum. Of course washing the cage with some mild detergent washes away any scent trails the ants have left, so that others don't return and you'll have a repeat performance! After doing that, I would address the ant problem itself (such as killing them and washing the entire ant trail with soap to eliminate scent to keep others from entering your house/building) . Just curious, was there any (dead) food left in the cage - OR candy bits/crumbs spilled by kids??? All it takes is crumbs!
Good luck
Zee
I'm an expert on everything, but know so little and have so much to learn - Carsten Zoldy -