It depends on the goldfish.. For ones that stay small you should have at least 10 gallons.. The bigger the goldfish gets the more water it needs. Those one and two gallon bowls do not cut it..
Goldfish don't need salt because they are Freshwater Fish!
Because a comet is a single tailed goldfish, and can grow very long, it will need at least 30 gallons on it's own
About 2/3 or 3/4. Basically depends on the size.
You need to provide 1 gallon of water per inch of fish. Goldfish get along fine with other goldfish.
My Fantail Goldfish did that alot the first time I got him. I think it might be that they need to relax or they might be scared.
No, a goldfish will not kill a betta but they should NOTbe housed together. First of all, bettas are tropical fish, meaning they need temperatures of 75-85 F while goldfish are cold water fish and need much lower temperatures. Also, bettas are usually quite aggressive and territorial so I would not risk housing him with a goldfish.
Goldfish and turtles have different care requirements and habitat preferences. Goldfish need a tank with clean water and a filter, while turtles need a tank with both water and a dry area for basking. Goldfish prefer cooler water temperatures, while turtles need a warmer environment. Additionally, goldfish are primarily herbivores, while turtles are omnivores and require a varied diet.
HOPE THIS IS HELPFUL
goldfish will survive in tap water but it is best to put a bit of chlorine control in the water plus you will need a filter if you want the water and tank to stay cleaner for longer :)
your goldfish might die and maybe eat to much or the water starting to get dirty
It depends on the fish. If its a tropical fish that is accustomed to salt water, you need salt water and you need to keep the water at a warmer than norm temperature. If its just a regular goldfish, freshwater at room temp should do just fine.
Yes, like all pet fish, goldfish need more oxygen than can be provided by just a bowl of water.