Although this quest chain began via the Sea Collector, it continues by talking to the Sea Scholar.
When you give the Ancient Treasure Instructions to the Sea Scholar, choosing the dialogue option 'Ask about Ancient Treasure Instructions', he will tell you the following:
Ask about Ancient Treasure Instructions
Yes, can I help you? Ah, you'd like me to decipher some ancient text for you. Well I do pride myself on such abilities. However, as you know services around here aren't free. you'll have to do something for me first.
Recently in my old age I've been having a difficult time seeing. There is a tool called a magnifying glass that should help with my vision. If you bring that to me, I'll finish deciphering the text.
I hear you can find them in some pirate chests. Apparently there are captains who take a fancy to reading. Who would have thought?
Once you've found it, return to the Sea Collector, choosing "Deliver the magnifying Glass" and he will say the following:
Deliver the Magnifying Glass
Thank you for retreiving the magnifying glass! I have finished deciphering the text. Are you ready?
It appears that this ancient treasure spoken of was swallowed up by a creature conjured by the ancient ones. They brought forth such a beast by using a variety of rare herbs and potions to make a brew that would lure it here, but weaken the one who drinks it.
While you were gone I took the liberty of finding these ingredients and brewing the potion. Since you've done what I've asked, I will give you this potion. Be wary though, this foe will likely be difficult and the potion will likely damage you upon drinking it.