Assuming you mean Cyser and assuming it was pushing CO2 when you put it in there you're fine. But you will need top up (or purging) for future rackings.
I always make an extra quart to half gallon with wine for topping up. Then I clear off the lees in the fridge so I always have plenty of top up.
If you didn't do that what you could do if it went dry and you don't want it dry is wait until it's done fermenting, sulfite/sorbate and use apple juice to top up/backsweeten with.
Other options are sanitized marbles, wine (of a type that's fermenting, in this case apple wine).