Welcome to the Candy Crush Saga Community
Do you have a question or need help with your game? Ask the Community.
I found this on the Wikia page for the level:
"Activating one Jelly Fish should be enough. The third sub-fish from the first fish should eat the second fish from the other sugar chest, though this might not always happen. For example, moving the purple wrapped candy up on the board to the right will get the fifth key, blow up the right fish, which will then eat two jellies and should also eat the left fish, which will then finish the level on that move. However, activating two fish at the same time will leave jelly on the board."
If you wanna see the screenshot for the message above it's in the Strategy section: http://candycrush.wikia.com/wiki/Level_1351