I dropped 5 crappie condos today in about 9 feet of water... That is the deepest point of an area I fish.

The condos are roughly 5 feet tall.

Made of a plastic bucket filled with concrete holding the PVC slats.

I didnt take my GPS with me because I figured I had my depth finder.

Anyways after dropping them I couldnt see them on my depth finder

As I made repeated circles around where I know they are I really seen nothing.
A few bumps on the bottom......

Now on my rowboat I have a Hummingbird fishing buddy 100 not the best but it does work... The beam is straight down.

Again Im in 9 feet of water and the condoes are 5 feet tall.
I set the sensitivity to the highest and zoomed in to 9 feet. Again just a few bumps.

I rowed over to where I know there is a log underwater and it picked that up fine.

So my guess is it might have major issues picking up plastic ?????? I guess

Any Ideas ?