What it is
Sweetcorn is a banker for tench and carp, a change bait for F1s, and a way of dodging tiny roach when maggots are getting slaughtered. It is visible, it tastes of something, and it hair-rigs without fuss.
Use it straight from the tin, washed if you want less juice in the swim, or a grain on a hair. Two grains for carp and tench; a single grain for F1s and better roach. Plastic corn is a useful stand-in when the real stuff is coming off or the skimmers are a pest.