Hello aspirant,
Hope you are doing great. So, in general to do MSC in aquaculture one must and should finish his or her Bsc in fisheries. Then only they will be eligible to do MSC in aquaculture. Also, if you had completed Bsc in zoology also you will be eligible. Many of the colleges does not accept Bsc chemistry students to do MSC in aquaculture.
Hope it helps you,
Good luck, Thank you.