I don't do social media, YouTube included, nor do I understand which video should the players comment (the above link leads to Plarium's channel, not a video). Anyway, since we already had this puzzle, let me help my fellow pirates: 81.
A ship is obviously 20. So, a squid is (30-20)/2 = 5. However, notice that it has 5 arms, and the one below has 4. This is a "trick", so the one below is 4, not 5.
From the 3rd equation, we see that two barrels are 5-3=2, so a barrel is one.
Finally: 1+20*4 = 81 (before anyone asks... no, 1+20*4 is not (1+20)*4 = 84 :-P).
Good luck with rubies.