what kind of fish is good bait for coons or are they not to picky?

Any to be honest. Really you'll have better luck using something sweet to lure them though. I like using a Krispy Kreme donut with the jelly filling and the white frosting stuff on them. I found those work extremely well. The problem with fish is they attract cats and skunks. The sweets don't. However if you are in an area with Bear all of these baits tend to attract them as well. Are you trapping these animals or hunting them?

i use a can of tuna open it and leave the lid in it so they have to work to get it assuring they set the trap

I quit using fish(sardines) it attracts possums and others,,I started using Peanut Butter. Still up in the air if they perfer crunchy over creamy.