[Paddlewise] kevlar and water

I have a kevlar Necky and have noticed that when water is left in the cockpit overnight 
or longer there is a white surface that appears on the kevlar lining.  This white surface 
strongly adheres to the kevlar and remains even after the water is removed and the 
boat dried.  Does anyone have an idea as to what this might be?  How to remove it?  Is 
it bad?

***************************************************************************
PaddleWise Paddling Mailing List - All postings copyright the author and not
to be reproduced/forwarded outside PaddleWise without author's permission
Submissions:     PaddleWise_at_PaddleWise.net
Subscriptions:   PaddleWise-request_at_PaddleWise.net
Website:         http://www.paddlewise.net/
***************************************************************************