Did I make the wrong play here or did he chase too hard?

Any card but a fucking Spade on the river. I thought I gave him terrible odds to call but this was just frustrating.

PokerStars Game #4500981740: Hold'em No Limit ($0.25/$0.50) - 2006/04/02 - 19:55:45 (ET)
Table 'Eugenia IV' 6-max Seat #1 is the button
Seat 1: creed616 ($16.65 in chips)
Seat 2: sasifricious ($55.80 in chips)
Seat 3: DeweyG ($42.10 in chips)
Seat 5: johnnyBuz ($48 in chips)
Seat 6: smellycat04 ($20 in chips)
sasifricious: posts small blind $0.25
DeweyG: posts big blind $0.50
smellycat04: posts big blind $0.50
*** HOLE CARDS ***
Dealt to johnnyBuz [Ah Kh]
johnnyBuz: raises $1.50 to $2
smellycat04: folds
creed616: folds
sasifricious: calls $1.75
DeweyG: calls $1.50
*** FLOP *** [Ks 2s 4s]
sasifricious: bets $1.50
DeweyG: calls $1.50
johnnyBuz: raises $4.50 to $6
sasifricious: folds
DeweyG: calls $4.50
*** TURN *** [Ks 2s 4s] [4d]
DeweyG: checks
johnnyBuz: bets $8.50
died eye joins the table at seat #4
DeweyG: calls $8.50
*** RIVER *** [Ks 2s 4s 4d] [As]
DeweyG: checks
johnnyBuz: checks
*** SHOW DOWN ***
DeweyG: shows [8s 8d] (a flush, Ace high)
johnnyBuz: mucks hand
DeweyG collected $35.20 from pot
*** SUMMARY ***
Total pot $37 | Rake $1.80
Board [Ks 2s 4s 4d As]
Seat 1: creed616 (button) folded before Flop (didn't bet)
Seat 2: sasifricious (small blind) folded on the Flop
Seat 3: DeweyG (big blind) showed [8s 8d] and won ($35.20) with a flush, Ace high
Seat 5: johnnyBuz mucked [Ah Kh]
Seat 6: smellycat04 folded before Floph

You played it fine for the most part. I would have made a much larger turn bet of around $15. He was a donkey for sticking around and trying to catch his 8 high flush which often times will be no good even if he hits. Where it mattered you got unlucky, but in future hands make bigger bets of 60% the pot at least.

$6 in pot preflop
flop: leads out for $2, gets another caller before it's your action to make it $10, so bet that amount, about $9-10
turn: bet 3/4 to full pot again
river: great check behind as played, he chased and you didn't reward him any more. you knew what he had and didn't make his play on previous streets by checking behind.