$2 NLHE Full Ring: 3-betting a fish, please help me with bet sizing

[Stu_Ungar]

The reason I flat here sometimes is that he made it 5x instead of 3 or 4x. I think I 3bet 100% of the time if he makes it one of those amounts. With a 5x our 3bet creates a pot so big that I don't want to fold very often postflop which puts me in some difficult spots on Axx and Kxx boards.

Why are you in a difficult spot on Ax or Kx boards?

make a small bet or just check it down. He isnt going to see you bet 10c into an 80c pot ant think "thats a hand like QQ I'm going to bluff with my 77" he is going to look at his cards, make silly calls with jack high and 22, call down with some Ax and raise his big hands.