I recently found a 17 litre (4.5 gallon) tank in my grandparents garage and wasn't sure what to do with it. It's pretty dirty and even had plants growing in the old filter compartment but do you think I could clean it up and set up a tank before the babies are born?
Maybe move the fish out temporarily to the new tank, and leave the more sensitive shrimp in their current home?
A big bundle of moss or subwassertang makes a great hiding place for new born shrimplets. With any luck you won't see them for the first week or two, and neither will the fish!