Chubasco Deep Sea Fishing - Gratuities

[5:00 Somewhere]

Based off of reviews I've read on the message board, we have booked Chubasco to go deep sea fishing while in Nassau. Just received the confirmation, and noted is that "the price does not include gratuities for the captain and mate. The customary tip is usually 15% of the charter cost." My question is does each one get 15% (which would essentially be 30% for 15% x 2) or 15% total and they split it? Your insight would be appreciated!

[runner15km]

15% for Captain and 15% for each crew member.