As mepperson posted you will need to take great care to remove all the off color meat. After filleting then cut the grey out that was between the meat and skin. Then make sure any blood line is removed.
Salt water will work but I have also used milk.
Those look just like a fish we call White Bass in Wisconsin and I have caught many thousands over the years, because in the spring they run up rivers to spawn and no bag limit is imposed. It's not unusual for boats to have hundreds of them but cleaning them is work. After eating other fresh water fish you will not like the taste of these unless you take the extra care to do as posted in our reply’s.
Next time you are on the water look for jumping minnows and cast small spinners into that commotion and you will have a blast.