Turn bet size?

[jusander]

Should I just bet the pot or go all-in in this, there is a flush draw but it's somehow unlikely, 'cos AK is on the board. Is this bad?

PokerStars No-Limit Hold'em, $0.25 BB (6 handed) FTR converter on zerodivide.cx

UTG ($5.95)
MP ($28.85)
CO ($18.10)
Button ($21.90)
SB ($6.20)
Hero ($23.95)

Preflop: Hero is BB with A[img]/images/graemlins/spade.gif[/img], K[img]/images/graemlins/diamond.gif[/img].
<font color="#666666">2 folds</font>, CO calls $0.25, Button calls $0.25, SB completes, <font color="#CC3333">Hero raises to $1.5</font>, CO folds, Button calls $1.25, SB folds.

Flop: ($3.50) A[img]/images/graemlins/club.gif[/img], 8[img]/images/graemlins/club.gif[/img], 4[img]/images/graemlins/spade.gif[/img] <font color="#0000FF">(2 players)</font>
<font color="#CC3333">Hero bets $3.5</font>, Button calls $3.50.

Turn: ($10.50) K[img]/images/graemlins/club.gif[/img] <font color="#0000FF">(2 players)</font>
<font color="#CC3333">Hero bets $18.95 (All-In)</font>, Button folds.

Final Pot: $29.45
<font color="#009B00">Main Pot: $10.50, won by Hero.</font>
<font color="#009B00">Pot 2: $18.95, returned to Hero.</font>