Snails are known to eat small prey if they can get to them, but fry will be able to outswim them before being killed.
No, they will eat them.
Looking online suggests that both Chinese Mystery Snails and Banded Mystery Snails are edible. Both are invasive where I live and I recently grabbed a few to eat. A word of caution, all wild caught snails must be kept for a few days (3-8) with constant changing of their water, tap water will do, to rid them of any toxins they picked up. Feed them oatmeal, cornmeal, or lettuce to get the mud they have been previously been feeding on out of their systems.
Maybe if they're dead! Snails generally just eat... whatever else the fish don't. Snails will make quick work of a dead fish, though.
It depends on which catfish, bristle nose catfish do fine with guppies.
Guppies are tropical fish and should be kept around 70F to 75F.
The goldfish should never be in the same tank as guppies. Goldfish are coldwater fish and need to be kept below 70F. Guppies are tropical fish and need to be kept above 70F.
Snails can be kept as pets.
They should never be in the same tank because Guppies are tropical fish and like to be kept over 70F and Goldfish are coldwater fish and like to be kept below 70F. So Goldfish should not bite guppies because they should never be in the same tank together...
Guppies are very tolerant fish but they should not be kept with more boisterous fish. Also, guppies should not be kept with fin-nippers. Other live bearers make excellent tank mates.
Guppies are community fish that should never be kept alone or in bowls they require large tank, at least 10 gallons.
Sometimes but not really.
Goldfishes and guppies should be kept in a different tank....