Hints and tips for level 1236 Candy Crush Saga
You need to clear all the jelly before you release the fish, so that the fish will go to the two top squares which have no candies in them.
If you release the fish too early it may go to other jellies and leave the top ones alone, which will make them almost impossible to clear.
Without the fish the only way to hit those top squares is with a stripe/wrap combo along the side.
Video below by Skillgaming