Perch or Crappie on fish finder?

I have a lowrance elite 3x (only sonar) and the last few trips on my kayak have been a lot of fish finder practice. Is there any kind of hints whether or not what I'm seeing on my finder is perch or crappie? I mostly have been looking for a good school of fish on the finder then catching 1 or 2 to see if I guessed right but haven't really nailed down anything specific.

I think I've noticed perch show up as a massive blob on my screen (I figure its because they move so fast) and crappie seem to be a little more spread out and each fish more defined (they move slower?)

Also, if I'm on my kayak, should I set my ping speed to be slow when I'm just paddling slow? My idea is fish that are moving very quickly with my ping speed set the fastest wont really show each fish since their moving so fast.

Thanks everyone in advance.

LOL they can't swim fast enough to avoid the sonar beam. Just have to practice and like you said, catch a few and note what they looked like on the screen. Sometimes the schools are mixed. One of my friends was in Alabama last week and saw some fish schooling on top. He eased his way over and saw a huge school under the boat. He ended up catching 7 different species of fish out of that school. Perch, LM, Crappie, Catfish(2 types), White Bass and Warmouth. He had never seen anything like that ever! :yikes

Most of the time white perch will appear as more of a really tight school very close to the bottom. Crappie will be more individual marks and not as tightly schooled. This is not always true though.

The only time I feel relatively confident on the species is when I see the tight pattern on the bottom which is usually a school of white perch. However, several catfish have come out of patterns like that, so it is not an exact science.

I turn my chart speed down when going slow. There are a number of good video's on Youtube that can help out.

I have seen what I thought was the " cordwood" stacking of crappie.
_-
_-
_-
_-

Something like that. This may carry on for fifteen feet or so. If it is crappie, that's a weird behavior!

*** Those tics are supposed to be offset to look like a stairstep. The editor won't allow the blanks.

I agree with Yadkin Guide. The group of perch will be holding ver close to the bottom most of the time. They almost will look like a bunch of structure on the bottom. Crappie this time of the year will be a little more scattered most of the time. The shad are forming huge balls moving into the creeks this time of the year. I went over a few yesterday that covered almost the entire screen. Easy way to find out. Drop a minnow and see what bites. lol.