I also participated in raising FMH for NPDES toxicity testing in Pittsburgh. Kartracer used words of cut pipe, caves, and tiles all as the same thing. Pieces of 4" dia PVC pile were cut in 1/2 to make two C shaped pieces of PVC caves for the fish. Females would lay eggs on the inside upper side of the caves / 'tiles'.
As an example see this sexy FHM video
https://www.youtube.com/watch?v=JBoO-tFrbJg

Last edited by Bill Cody; 01/19/16 08:02 PM.
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