Either an aquarium or a pond. NO BOWLS, PLEASE!
All goldfish are freshwater.
The same way you spawn any other goldfish.
Fantail goldfish are a hardy breed, strong swimmers and they compete well for food with the ryukin, shubunkin, comet or common goldfish; making these goldfish breeds good tank mates for your fantail goldfish.
Yes, but only for a very short time, for goldfish are known to grow rapidly.
Common types of goldfish available at pet stores include the Comet, Shubunkin, Fantail, Oranda, and Ryukin.
Yes, but it might be better for the fish to have a tank partner by its side. Make sure it is another Fancy Varitey of Goldfish!
Yes, but your tank size needs to support it. If you mean that a regular goldfish is a long single-tail goldfish, then you need at least a 40 gallon tank just for the 2 fish due to the size potential of the common goldfish. If you mean a regular goldfish as in a round bodied fantail, or perhaps a ryukin, then you need at least a 30 gallon tank for the 2 fish.
The only issue I've heard about concerning housing goldfish together is any big difference in body shape or size. Bigger goldfish might be more aggressive towards smaller goldfish. Also, the more streamlined breeds (koi, comet, etc.) might have an easier time snatching up food, leaving little behind for the pudgier, slower fish (fantail, ryukin, etc.).
Yes, for they are both Fancy Goldfish (It's bad to keep Comets with Fancy varities because most likely the comet will become stressed and die).
the common breeds of goldfish are common, shubunkin, fantail, black moore, orlanda, sarsha comet, comet, ryukin, bubble eye, lion head, rancho, veiltail, celestial, pom pom, and perlscale are the most common.
another gold fish or try asking someone in a pet shop that sells fish maybe they can help
There are over 300 different varieties of goldfish and fancy goldfish here is a small list of the most common: Common goldfish Shubunkins Comets Fantail Veiltail Ryukin Globe eye Black moor Telescope eye Lionhead Ranchu Oranda Butterfly Celestial Pompon Hama Nishiki Bubble-eye Pearlscale Nymph Meteor Lionchu