For best results, seahorses sould be preserved in formalin first, to harden
the tissues.  Position the head and tail the way you want them to look in the
finished specimen - straight or curled, before you put them into the formalin,
because they won't be flexible afterwards.  Then the excess formalin should be
washed out with water or alcohol, and the specimen dried.  The resulting
specimen will be odorless, hard, and quite resistant to breakage.  A seahorse
can be dried directly, without prior chemical preservation, but there will be
greater shrinkage and distortion.
Paul M.