What you post is in many ways ambiguous.
Let's say you put 1000L of the solution in the 1000L tank. Tank is full, no headspace over the liquid, question about the amount of the gas is a moot.
Let's say you put 1000L of the solution in the very huge tank, thousands of cubic meters. Chances are everything dries out, amount of ammonia emitted is that of the ammonia present.
These are equilibirum conditions, where things can be calculated. And if your question is about how much ammonia is lost during a transfer, when for some time some of the liquid is in contact with air, some is in the tank, and at no point system is in the equilibrium, then the answer is: no way to calculate anything.