One little precision here I'm mainly a largemouth bass fishermen.
For bottom feeders like catfish and carp Atractant might be more effective than for a bass. So they are equiped with barbs and have a much more developped sense of smell than sight feeders.
Catfish will eat dead meat/fishes and live minnows, crayfish etc
My late grandmother told me that when she was a teen she was swimming in a lake in the Laurentian and she saw a dead horse in about 8 ft of water and there was about a hundred catfish eating the carcass
She never did eat catfish again
Carp most of the time will go for vegetal stuff ( ok I know about carp eating fish eggs...)
Personnaly we did a test to attract carps with greasy to the point of stating sweet french fries
and it worked!
The europeans use a mix of potatoes oil and glazing sugar and other stuff to make a dough to catch carp.
LL
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