I'd pick and chose swims and species on a canal if I wanted to fish a feeder. Generally, less intrusive methods and lighter gear tends to work a lot better.
That said, one good use for feeder fishing on a canal would be for bream. Find a wide section - a turning bay, boat moorings if permitted etc - and it's likely to hold bream and the advantages of a feeder come into play: you can fish further out than pole anglers, hold a bait still more easily than a waggler, and put your feed and hookbait together.
I wouldn't bother casting right to the far bank, even if it's possible. Better to fish in deeper water where bream like to be. I'd choose somewhere the far side of where the boats come through so they don't disturb your fish and your feed so much in 3 or 4 feet of water.
A light, soft rod with a fine tip suits the job, and a small open-end feeder. Cast every few minutes for the first hour, or until you get bites with chopped worm and casters in your groundbait. On the hook, live or dead maggots, pieces of worm, pieces of worm with a maggot or caster.... all kinds of things work, and it's worth trying different hookbaits as these fish can have unpredictable preferences.
I wouldn't really try it on hot, still sunny days like today. It's a good method for a dull, damp and windy day when the bream will feed and be less cautious and other methods are made hard by the conditions.
But I don't know what's in your canal, so you might chuck a bread feeder over to the rushes and get a big carp or a chub. It's a tried and tested method for bream on the wides, though.
