To access the lower part of karikiro spring place a bomb beside the boulder near the entrance to karikiro village if ther is a chiken in side your at the right place follow the passage untill you get to back of the spring(lower part) cast your rod in to the spring you will reel in a bag of rupees after you reel in the bag of rupees you will find hyrule bass and possibly a hylian loach.
This information has been submitted by DC&DB