I'm with Tony, I'd take the corrector off pronto and let the thing dry out thoroughly. Removing the corrector plate is easy, I had to do it to retighten a loose secondary holder, the plate should have alignment marks, if not put a small mark at the outside of the plate and on the tube to indicate alignment. It won't be necessary to remove the secondary from the plate but if you do make sure that is marked for alignment as well. Whatever you do don't leave the water in there, it takes no time at all for mould to form and the any form of mould usually will result in permanent damage. I'd be trying to work out where the water has come from, I've never had any moisture at all inside my SCT OTA. Here's a
page on corrector removal from Jan's LX site