I can't decide what to do on river

[tyrn]

Villain is 30/15 over 30 hands

Full Tilt No-Limit Hold'em, $0.02 BB (6 handed) - Full-Tilt Converter Tool from FlopTurnRiver.com

BB ($2.15)
UTG ($2.49)
MP ($2.46)
CO ($3.94)
Hero (Button) ($2.03)
SB ($1.76)

Preflop: Hero is Button with K, A
UTG calls $0.02, 1 fold, CO calls $0.02, Hero bets $0.10, 3 folds, CO calls $0.08

Flop: ($0.25) 10, J, Q (2 players)
CO checks, Hero bets $0.20, CO calls $0.20

Turn: ($0.65) J (2 players)
CO checks, Hero bets $0.40, CO calls $0.40

River: ($1.45) A (2 players)
CO checks, Hero ?

I think theres lots of Qx and Jx in his range so checking misses a lot of value. At first I want to b/f. But then what if he raises with a king? Lots of kings in his range. I don't feel good about bet/call since i'm not sure about this opponent's tendencies. So go for value, or protect the stack?

[StarGrinder]

Bet for value. There's a lot of worse hands that a 2nl fish will call with here. Villain never plays like this with better hands unless he's missing a chromosome. Worst case scenario he's got a K for the chop.

[spoonitnow]

Step 1: Put your opponent on a range.

[tyrn]

Bet for value. There's a lot of worse hands that a 2nl fish will call with here. Villain never plays like this with better hands unless he's missing a chromosome. Worst case scenario he's got a K for the chop.

I think you're right, just because I wouldn't call doesn't mean they wouldn't.

[Carroters]

Just b/f this river for value maybe like 60c, we don't want to make it too big since we need to give the weak hands in his range a decent price, if he raises he'll have a boat almost always, but can still call with 2 pair hands and trips.

You need to be betting this turn harder, just pot it. He's folding close to 0% of his range on this card and you're actually missing valuye from draws Jx Qx etc etc when you only bet 3/4 pot. The bigger your turn value bet, the better odds you can offer him on the river, since he's never folding this turn, you're aswell going down this route.