Adam Clarke on Ezekiel 29:4

I will put hooks in thy jaws - Amasis, one of this king's generals, being proclaimed king by an insurrection of the people, dethroned Apries, and seized upon the kingdom; and Apries was obliged to flee to Upper Egypt for safety.

I will cause the fish - to stick unto thy scales - Most fish are sorely troubled with a species of insect which bury their heads in their flesh, under their scales, and suck out the vital juices. The allusion seems to be to this. Pharaoh was the crocodile; the fish, the common people; and the sticking to his scales, the insurrection by which he was wasted and despoiled of his kingdom.