Fact
Fish can be unintentionally killed if their owner smokes. Gulp.
Source 1:
Axelrod, Herbert R. et al. Dr. Axelrod’s Mini-Atlas of Freshwater Aquarium Fish. 1987 p. 827.
http://www.hsvma.org/secondhand_smoke_harms_pets_and_wildlife#.Vow1wGS-mko