eventually, yes
Yes
Guppies, silver dollars, cherry barbs, and tetra are just a few. However what ever you do DONT PUT GOLDFISH WITH OTHER KINDS OF FISH they pee too much ammonia and will kill all of your other fish.
Yes, In general coldwater fish like goldfish are more hardy(harder to kill) than tropical fish. Saltwater fish are very easy to kill if you don't know what you are doing. Goldfish are very hardy fish that you can't kill easily. It is best to start out with fish like goldfish because you can make mistakes with them that would kill other fish. So goldfish are fish that does not die easily.
Yes. Goldfish have been known to eat other goldfish that are small enough to fit in their mouth.
Yes, they will do anything to survive they will even kill other fish for food or a house!
no
You should not put a male betta with goldfish's.They are aggressive and will fight with goldfish's goldfish give off ammonia and will kill the Betta's.
yes, leaches kill gold fish
large fish.
Enough food that they can eat within 1-2 minutes. Be sure not to over feed as this can cloud water or cause ammonia spikes which kill the fish
Goldfish are not aggressive fish. They most definitely do not kill people.
It would die. The ammonia would kill the fish if amounts were elevated.
The simple answer is yes. Just remember the golden rule 1 inch of fish needs 1 gallon of water.