Theo
Any chance that bathtub of yours is on the end of a dock full of bass and you're forcing them into cannibalism?
You know, I thought the first part of that - the bathtub holding tank on the dock - wasn't a bad idea. When I get a dock finished near where I fish at (current dock is on the opposite side of the pond) I may try that.
P.S. LMB are natural cannibals, just ask any fish farmer who has watched 1000 1" LMB turn into 100 3" LMB.