Unfortunately, Black Soldier Flies are not typically found often above USDA zone 7 (and rarely in zone 6). Even zones 6 and 7 have short seasons of just a few months in the summer when BSF can be found. Zone 5 in Iowa - sorry to say they aren't gonna be there. While I agree feeding BSF larvae is wonderful for the fish, the cost of importing sufficient quantities outside their native areas would be prohibitive.Originally Posted by rfeiller