It's 50/50 tbh mate. Ive had a pop-up in amongst particle mixes and had a carp every cast, whereas other times ive had nothing, but absolutely destroyed using sweetcorn, in exactly the same locations. So it really depends on the day. As for the pick ups and successful hooks, that is ultimately down to rig mechanics and having the hook set up properly with the bait your using. It's good to experiment and get your snood leaving the hook eye 100% straight, at a near perfect angle to get the hook to kick out and hook the lip on the bait ejection perfect every time. As for snails on pop-ups, I would imagine glue is used, although I've never done this myself. One thing you can do is thread a few hemp seeds to a bit of cotton using a thin sewing needle and attach this to the hair and/or hook. Ive had success with this too.
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