Bluffing a Callingstation at NL50

[TylerSoapCO]

Party Poker - No Limit Hold'em Cash Game - $0.25/$0.50 Blinds - 4 Players - (LegoPoker HH Converter)

SB: $42.56
BB: $54.70
UTG: $55.65
<font color="black">Hero (BTN): $47.65</font>

<font color="black">Preflop:</font> Hero is dealt Q[img]/images/graemlins/heart.gif[/img] K[img]/images/graemlins/heart.gif[/img] (4 Players)
UTG calls $0.50, <font color="red">Hero raises to $1.50</font>, SB calls $1.25, BB folds, UTG calls $1.00

<font color="black">Flop:</font> ($5) T[img]/images/graemlins/heart.gif[/img] 3[img]/images/graemlins/heart.gif[/img] A[img]/images/graemlins/diamond.gif[/img] (3 Players)
SB checks, UTG checks, <font color="red">Hero bets $2.00</font>, <font color="red">SB raises to $4.00</font>, UTG folds, Hero calls $2.00

<font color="black">Turn:</font> ($13) A[img]/images/graemlins/club.gif[/img] (2 Players)
SB checks, Hero checks

<font color="black">River:</font> ($13) 7[img]/images/graemlins/diamond.gif[/img] (2 Players)
<font color="red">SB bets $0.50</font>, <font color="red">Hero raises to $6.00</font>, SB calls $5.50

SB is a callingstation, and my bet on the river is intended as a bluff, but is this a total waste of money here his play confuses me he raises me on the flop and then he checks when an other ace comes which leads me to belive that he dosent have an ace. And me betting half pot bet should represent a ace even for a callingstation so he should only call here if he has a Ax or a set or what???

So what do you peopele think is my read of, and/or should i just give up and call his minibet.