A forever attractor...

Couldn't sleep 1 night and started conspiring to plan the baddest longest lasting multiple use attractor that could imagine. ( evil laughter sound effect here, please) that could be placed. Keep coming to the bottom half of a septic tank with upright cement blocks cemented to it stuffed with Osage orange branches and carrying dozens of 10 hole bricks cemented vertically to its sides with some PVC also in cement blocks cemented securely. tactically enhancing it. Tow this thing into place with another boat SLOWLY on an absolutely calm day and punch a hole in the bottom and watch it go to its final resting place... Thoughts ? Too extreme ? It wouldn't stay secret very long...

Lol to extreme for me. I just zip tie branches to concrete blocks or tie with a wire to a rip rap rock.

Should work but be careful . :twocents

Sounds like you just had a crappie habitat nightmare. "Build it and they will come":highfive

Funny you should mention this. I had a buddy that did just about what you are talking about a few weeks ago. minus the septic tank. ( this was his private lake )

Go for it!
Call a local septic company, or manufacturer of them, see if they have any rejects?

The capability exists locally, cost (?) and delivery would be the difficulty and the weather would have to be utterly calm... They might last beyond 30 years. Even 10 strategically placed would seasonally be very productive but would become magnets for fisher persons. Have to wonder if COE might be willing to get involved ? Ohio Dept of Natural Resources ? The Scouts ? Would ask the USAF for a hand but they are probably busy elsewhere world wide...