Take a Gee trap, paint it black and see how it does. To reverse it, you can repaint it galvanized.
https://www.rustoleum.com/product-catalog/consumer-brands/stops-rust/cold-galvanizing-compound-spray


www.hoosierpondpros.com


http://www.pondboss.com/subscribe.asp?c=4
3/4 to 1 1/4 ac pond LMB, SMB, PS, BG, RES, CC, YP, Bardello BG, (RBT & Blue Tilapia - seasonal).