you need to get a bigger cage much sooner then that. when the teil eggs hatch you will have ::cue drumroll:: 4 or more tiels in that one tiny not even big enough for one tiel cage.
that's not fair
if you didn want to spend the time or money to find them a better cage you shouldn't have taken them or bred them. Keep in mind you'r e risking their health for your amusemtn the least you could do is get them a bigger cage now and get it ready for as soon as they can be moved.